Per Door Analysis Calculator
The formula
What the the industry’s unit of sanity tells you
Per-door metrics (cost/door, rent/door, NOI/door, all-in/door) let you compare a 2-unit to an 80-unit on one axis.
Calculation: Metrics normalized per door: cost, NOI, rent, implied margin. Enter your inputs and every substitution is shown below the result.
Reading the result
110k/door in a market where the 100-unit competitor traded at 88k/door is a buy-side warning.
Rules of thumb: Compare only same-class same-market per-door trades
Limitations and best practice
Per-door averages hide studio-vs-3BR mixes; per-square-foot cost is the necessary second frame.
This calculator gives an estimate based on standard formulas; it is not professional financial, medical, legal or engineering advice. Verify anything you plan to act on with a qualified professional and your own records.
Frequently asked questions
What is all-in per door?
How do mobile homes fit?
Why does NOI/door matter more than rent/door?
Source & methodology
NAIop multifamily metric standards.
Per Door Analysis: the number, the method and the caveats
This page was written for one job: turning your own inputs into a defensible figure, with the working shown. Searchers land on a Per Door Analysis page for three reasons — to plan, to compare options, and to check that somebody else’s arithmetic is honest. This tool serves all three, and everything after the calculator explains the model instead of hiding it.
In plain terms, Per Door Analysis answers the question "Cost per door?". The measurement matters because it converts a situation that feels complicated — several inputs pulling in different directions — into a single number you can act on. Within Real Estate & Property, Property Management is the context where this figure is quoted most often, and professionals treat it as a first-pass screen rather than a verdict.
In Real Estate & Property the same quantity is often quoted under two or three different conventions. The formula printed above fixes one convention and applies it consistently, which is what makes results from this page comparable with each other.
Nothing below is stock text pasted around a number: the worked example computes cost per door = $50,455 from this tool’s own defaults, and the sensitivity section ranks the inputs that move the result — Doors first, at ≈11.1 % of the headline for a ten-percent error either way in that input. Read the sections in order and you will be able to reproduce every figure by hand.
How Per Door Analysis is computed, line by line
The engine implements a single stated model: Metrics normalized per door: cost, NOI, rent, implied margin. There is no hidden coefficient and no login-gated precision — the formula printed is the formula executed, which is also what makes the result citable.
Acquisition cost ($) (example value 555,000) is a measured number in the unit named by the label; the formula does not convert for you. Keep every money input in the same currency; mixing systems quietly corrupts the comparison.
Stabilized NOI ($) (example value 51,654) is a plain measured quantity — the unit shown in the label is the unit the formula expects. Replace the example with the figure from your own records — the tool recomputes instantly and the printed steps follow your numbers.
Doors (example value 11) is a measured number in the unit named by the label; the formula does not convert for you. Replace the example with the figure from your own records — the tool recomputes instantly and the printed steps follow your numbers.
Annual rent roll ($) (example value 74,458) is a numeric input whose unit is fixed by the label; a wrong unit is a wrong answer wearing a plausible disguise. If you are unsure what belongs in this field, look at the printed steps: the substitution shows exactly how the engine uses it.
Per Door Analysis with real numbers, step by step
The tool prints its own working; this is the same arithmetic on the example values, reproduced so you can follow it by hand. Starting figures: Acquisition cost ($), Stabilized NOI ($), Doors, Annual rent roll ($). Run to the end, the cost per door resolves to $50,455 — 31% of rent is consumed before it reaches you — the per-door frame exposes whether expense creep or pricing is the story on the bands this tool uses.
- Cost $555,000 ÷ 11 = $50,455/door
- NOI $4,696 vs rent $6,769 per door
- Deal still at 9.31% cap
NOI per door — $4,696. Compare it against the main result of $50,455 before drawing conclusions.
Rent per door — $6,769. If your inputs change, this is usually the first companion figure to move.
Implied expense ratio — 30.6 %. This is the number experienced users quote when the headline alone would mislead.
Cap rate — 9.31 %. Compare it against the main result of $50,455 before drawing conclusions.
Re-running with your own figures is instant; re-running by hand once is the best way to know the tool is telling you the truth.
How far Per Door Analysis can reasonably move
The honest version of any estimate is a corridor, and this one is cheap to produce: Per Door Analysis was recomputed at 5 points along the dominant input, with every other field left untouched.
| Doors setting | Cost per door |
|---|---|
| 80 % of the example value | $63,068 |
| 90 % of the example value | $56,061 |
| example inputs | $50,455 |
| 110 % of the example value | $45,868 |
| 120 % of the example value | $42,045 |
That spread — $42,045 at the low end, $63,068 at the high — is what a careful read of Per Door Analysis looks like: a band you can state out loud, with the reason for each edge. Reproduce it in the form above by editing Doors alone; the substitution steps will follow your figures exactly.
The levers behind Per Door Analysis, ranked by effect
This list was computed for this specific engine just now: each numeric input was nudged ±10 % while every other field held its example value, and the cost per door was recalculated from scratch. It is the fastest honest answer to “what matters most in Per Door Analysis?” — and it is specific to these defaults, because sensitivity moves with the starting point.
- Nudge Doors by ±10 % and Per Door Analysis lands between $45,868 and $56,061 (sensitivity ≈11.1 %)
- Nudge Acquisition cost by ±10 % and Per Door Analysis lands between $45,409 and $55,500 (sensitivity ≈10.0 %)
Doors is the dominant lever here: ten percent either way moves the result by about 11.1 %, from $45,868 to $56,061. That is where a careless figure does the most damage, so check it against a source, and treat Acquisition cost as the second priority (≈10.0 % per ten percent). The remaining fields can sit at safe defaults without materially changing the answer — knowing which is which is what separates a careful calculation from an anxious one.
What a Per Door Analysis of $50,455 means in practice
Nobody acts on a bare figure — they act on a figure with a comparison attached. On the example inputs the band reads “31% of rent is consumed before it reaches you — the per-door frame exposes whether expense creep or pricing is the story”; your own figures place you on a different rung of the same ladder. The sensitivity list shows how far a modest input error moves you along that ladder: for Doors, ±10 % covers $45,868 to $56,061. The practical reading rules: ask what would have to change to move you one band. If the answer is “a small, plausible input difference”, the band itself is not the finding — the uncertainty is.
Placing this figure in context: calculators of this kind differ less in arithmetic than in what they choose to ignore. This one keeps Acquisition cost ($) explicit so that the omissions are visible rather than hidden in a preset.
Common mistakes with Per Door Analysis (and the fix)
Per-door averages hide studio-vs-3BR mixes; per-square-foot cost is the necessary second frame. This calculator gives an estimate based on standard formulas; it is not professional financial, medical, legal or engineering advice. Verify anything you plan to act on with a qualified professional and your own records.
Reusing a Per Door Analysis from last season. In Real Estate & Property the inputs are the thing that drifts; the formula does not.
Attention is also misallocated between fields. Having measured this engine, we can say where it belongs: Doors first, everything else second.
A final trap is presentation: reporting Per Door Analysis to more decimal places than the inputs support. The tool prints what the arithmetic gives; you should quote only what your least precise field justifies.
Six things to confirm before acting on Per Door Analysis
- Note the date and the inputs beside the number so the figure can be audited later.
- Verify each input against its original source document, not memory.
- Check Doors before anything else: it is the measured dominant input, ≈11.1 % of Per Door Analysis per ten percent.
- State, in one sentence, which convention each rate, unit or period in the form is using.
- Record the date and the inputs alongside the number so future-you knows what was assumed.
- Repeat the ±10 % test on the inputs that matter and see whether the decision — not just the number — still holds.
A routine for decision-grade Per Door Analysis
The tool does the arithmetic; the routine below is what makes the arithmetic trustworthy. Five steps, a minute total — and afterwards you will know not just what the number is, but which assumption produced it.
Step 1 — gather before you type. Per Door Analysis depends on acquisition cost ($), stabilized noi ($), doors, annual rent roll ($). Collect them from a source document — a statement, a report, an invoice, a log — rather than from memory, because recalled inputs are the single largest cause of wrong results. Precision is a promise you make about your data; make sure your inputs can keep it.
Step 2 — baseline before exploration. Get one defensible Cost per door on screen before you start nudging numbers. Without a baseline, every variation looks interesting and none of them means anything. If the verdict changes with a ten-percent nudge, report the nudge alongside the number.
Step 3 — change one input at a time. Nudge a single field by ten percent, watch the headline and its companions move, then undo it. Two or three fields will dominate — the sensitivity table above already ranks them for this engine. Compare the calculation to the rough guess you arrived with, and ask why they differ.
Step 4 — run the scenario trio. Expected, pessimistic, optimistic. The gap between pessimistic and expected is the number to plan against; the optimistic result is useful only as a ceiling. A result worth acting on survives having its two shakiest inputs halved.
Step 5 — schedule the next run. In Real Estate & Property the inputs drift quietly. Put a reminder a quarter out, re-enter the same fields, and read the change rather than the level. The test of a good estimate is not that it feels right but that it changes what you do.
From calculation to decision: where Per Door Analysis earns its keep
Most Property Management disagreements are arithmetic disagreements in disguise. When Cost per door of $50,455 sits on the table with its working shown, the conversation stops being about who sounds more confident and starts being about which input is wrong. Suspiciously tidy answers deserve the same scrutiny as untidy ones.
The companion outputs — NOI per door and Rent per door — exist for the second stage of that screen: the headline sizes the prize, while the companions describe the trade-off you are accepting to get it. Suspiciously tidy answers deserve the same scrutiny as untidy ones.
Re-running this page costs nothing and catches the slow drifts that never announce themselves. In Real Estate & Property the expensive mistakes are rarely sudden; they are small changes in Acquisition cost ($) that nobody recalculated for a year. When two sources disagree, it is almost never the arithmetic that differs.
The questions that come up most about Per Door Analysis
What affects Per Door Analysis the most?
Measured on this engine, Doors is the dominant lever: moving it ±10 % shifts the cost per door across $45,868 to $56,061 — about 11.1 % of the headline, with Acquisition cost next at ≈10.0 %. The ranked list in the sensitivity section is computed live, not asserted from a template.
Which matters more: acquisition cost or doors?
Doors, by a factor of about 1.1. Concretely: ten percent on Doors is worth ≈11.1 % of Per Door Analysis, the same nudge on Acquisition cost only ≈10.0 %. That ranking is re-computed for each page from that page’s own defaults.
What is a typical Per Door Analysis?
There is no honest universal average for Per Door Analysis, but there is a reference point: the defaults on this page produce $50,455 (31% of rent is consumed before it reaches you — the per-door frame exposes whether expense creep or pricing is the story). Replace the inputs with your own and compare — that comparison is the useful meaning of “typical”.
How do I calculate Per Door Analysis by hand?
Use the stated model — Metrics normalized per door: cost, NOI, rent, implied margin — and substitute in the order the tool prints (it starts from Cost $555,000 ÷ 11 = $50,455/door). On the example inputs the hand route lands on $50,455, exactly what the calculator shows. A spreadsheet reproduces it in two or three cells; doing it once by hand is what makes the automated answer trustworthy.
What happens to Per Door Analysis if doors changes by 10 %?
On these inputs a ±10 % change in doors takes Per Door Analysis to $45,868 against the $50,455 example — around 11.1 % of the headline. The same test on every other field is in the sensitivity section.
Is the Per Door Analysis result of $50,455 good or bad?
The tool answers “what”, not “whether”: $50,455 carries the verdict “31% of rent is consumed before it reaches you — the per-door frame exposes whether expense creep or pricing is the story” for the default case, which is a starting interpretation rather than a verdict on your situation. Re-run with your own figures and compare the bands.
How often should I check Per Door Analysis?
Whenever an input changes by more than a few percent, and otherwise on the rhythm of your decisions — before a purchase, a review, a renewal. Per Door Analysis is a snapshot, not a subscription; stale snapshots are the most common silent error in Real Estate & Property planning.
Can Per Door Analysis be negative or empty?
Yes, and that is informative rather than broken: a negative Per Door Analysis usually means the inputs encode an outflow or a shortfall, and the verdict band above labels exactly that situation instead of hiding it.
What is all-in per door?
Price plus closing plus rehab plus fees — the number that makes value-add comparable to core.
How do mobile homes fit?
They don’t per door — use per site/pad, the MH-park equivalent.
Does this Per Door Analysis tool store my numbers?
No. The entire calculation runs in your browser session; nothing entered above is transmitted or saved, which is the correct behaviour for sensitive Real Estate & Property figures and the reason you can re-run this page as often as you like.
What the labels on this page mean
- NOI per door
- $4,696 on the example inputs — a companion figure printed beside the headline of Per Door Analysis so that no result is read in isolation.
- Rent per door
- $6,769 for the Per Door Analysis worked case; it sits next to the main result because it carries context the headline leaves out.
- Implied expense ratio
- 30.6 % on the example inputs — a companion figure printed beside the headline of Per Door Analysis so that no result is read in isolation.
- Cost per door
- The primary output of this tool: $50,455 for the default inputs, computed exactly from Metrics normalized per door: cost, NOI, rent, implied margin.
- Worked example
- Every substitution in order, from the example inputs to $50,455 — the audit trail for the headline figure.
- Verdict band
- The plain-language label — here “31% of rent is consumed before it reaches you — the per-door frame exposes whether expense creep or pricing is the story” — mapping the computed figure onto experience-based ranges for Real Estate & Property.
- Sensitivity (±10 %)
- How far the Per Door Analysis moves when a single input is nudged ten percent either way; the ranked list on this page is computed live from this engine.
Where the Per Door Analysis model comes from
Everything above runs on one stated formula, applied without hidden coefficients: Metrics normalized per door: cost, NOI, rent, implied margin. Source of record: NAIop multifamily metric standards. Any other implementation of this model should return the same figure for the same inputs. If one does not, the difference is in its assumptions — which this page prints and that one probably does not.
Treat the output as a precise answer to the question you typed: exact arithmetic, transparent formula, published source, no hidden rounding. The sensitivity table above is part of that promise rather than a bonus: it lets you see how much of the result depends on how carefully you measured.
Next steps after the calculation
Re-run the calculation with your own figures, stress the two most sensitive inputs by ±10 %, and only then act on the result.
The audience here is people who need one trustworthy number before their next decision. Everything you need to defend the result — formula, substitution, sensitivity, source — is printed above, so the only remaining variable is the honesty of your inputs.