Rex says
Money math without the spreadsheet headache. Plug in your numbers and I'll show you exactly where the dollars land.
Try a scenario
Click to load — tweak from there.Inputs
Result
Maximum offer built from real costs
$197,400
Offer from the rule of thumb
$183,000
How much the rule overshoots
-$14,400
Rule percentage your costs imply
74%
Selling costs at exit
$27,200
Non-rehab costs total
$47,600
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One click, a permanent link with your numbers baked in.
Got your number — what next?
Pick one, it takes 20 secondsHow to use this
- 1Enter after-repair value ($).
- 2Enter rehab estimate ($).
- 3Enter rule percentage (%).
- 4Enter target profit ($).
- 5Enter selling costs (% of ARV).
- 6Enter total holding costs ($).
- 7Enter total financing costs ($).
- 8Enter purchase closing costs ($).
- 9Read your maximum offer built from real costs on the right — it updates as you type.
- 10Hit Share to keep the scenario or send it to someone.
About this calculator
The 70% rule is shorthand for maximum allowable offer: 70% of after-repair value minus rehab. It is a screening tool rather than an underwriting model, because the right percentage varies with market, price point, and cost of capital — a low-priced property in a slow market needs a wider spread than a fast-turning one in a hot metro. This calculator computes the offer at your chosen percentage, then computes a second, cost-built offer from your actual selling, financing, and holding costs plus a target profit, so you can see how far the rule of thumb is from the truth on this specific deal.
Worked example
Using the values the calculator loads with:
Inputs
- After-repair value: 340000 $
- Rehab estimate: 55000 $
- Rule percentage: 70 %
- Target profit: 40000 $
- Selling costs: 8 % of ARV
- Total holding costs: 4200 $
- Total financing costs: 12000 $
- Purchase closing costs: 4200 $
Results
- Maximum offer built from real costs: $197,400.00
- Offer from the rule of thumb: $183,000.00
- How much the rule overshoots: -$14,400.00
- Rule percentage your costs imply: 74.2%
- Selling costs at exit: $27,200.00
- Non-rehab costs total: $47,600.00
What each field means
Inputs
- After-repair value ($)
- The after-repair value used in the calculation, measured in $. Starts at 340000 $ so you have a working example on load.
- Rehab estimate ($)
- The rehab estimate used in the calculation, measured in $. Starts at 55000 $ so you have a working example on load.
- Rule percentage (%)
- The rule percentage used in the calculation, measured in %. Starts at 70 % so you have a working example on load. Accepted range: 50–90 %.
- Target profit ($)
- The target profit used in the calculation, measured in $. Starts at 40000 $ so you have a working example on load.
- Selling costs (% of ARV)
- The selling costs used in the calculation, measured in % of ARV. Starts at 8 % of ARV so you have a working example on load. Accepted range: 0–20 % of ARV.
- Total holding costs ($)
- The total holding costs used in the calculation, measured in $. Starts at 4200 $ so you have a working example on load.
- Total financing costs ($)
- The total financing costs used in the calculation, measured in $. Starts at 12000 $ so you have a working example on load.
- Purchase closing costs ($)
- The purchase closing costs used in the calculation, measured in $. Starts at 4200 $ so you have a working example on load.
Results
- Maximum offer built from real costs
- Returned as a money amount in US dollars and shown as the headline result. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Offer from the rule of thumb
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- How much the rule overshoots
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Rule percentage your costs imply
- Returned as a percentage. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Selling costs at exit
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Non-rehab costs total
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
FAQ
Is the 70% rule still valid?
As a five-second screen, yes — it filters out obviously unworkable deals before you spend time on them. As an underwriting standard it is crude, because it bundles selling costs, financing, holding, and profit into one constant that does not move with rates or price point.
Why does my cost-built offer differ from the rule?
Because your actual costs differ from the ones baked into 70%. Expensive hard money, a long timeline, or high transfer taxes all push the true maximum offer below the rule; cash purchases and quick turns can push it above.
Should the rule percentage change with price point?
Yes. On low-priced properties, fixed costs consume a larger share of ARV, so investors often work at 65% or lower. On high-priced properties, the same dollar profit is a smaller percentage, and many operators go to 75-80%.
What if the seller won't accept my maximum offer?
Then the deal does not work at your cost structure, and the answer is to walk. The discipline of the maximum allowable offer is entirely in refusing to exceed it — every flip that loses money was purchased above one.
Accuracy and limitations
- Results are estimates before tax, fees, and inflation unless an input explicitly covers them.
- Rates are treated as fixed for the whole period — variable-rate products will drift from this projection.
- This is educational maths, not financial advice. Check anything contractual with the lender or your accountant.
Related tools
Cite this calculator
Writing about this topic? Grab a citation — every link helps keep these tools free.
RevenueLab. (2026). 70% Rule Maximum Offer Calculator. Retrieved from https://www.revenuelab.fyi/toolbox/seventy-percent-rule-offer
<p>Source: <a href="https://www.revenuelab.fyi/toolbox/seventy-percent-rule-offer" target="_blank" rel="noopener">70% Rule Maximum Offer Calculator — RevenueLab</a> (2026).</p>
Source: [70% Rule Maximum Offer Calculator — RevenueLab](https://www.revenuelab.fyi/toolbox/seventy-percent-rule-offer) (2026).