Underwrite your next flip — purchase, rehab, holding, ARV, and net profit, all in seconds.
Plug in purchase price, rehab budget, holding costs, financing, and ARV. Get net profit, cash-on-cash ROI, and the 70% rule max offer — instantly, no signup.
Direct answers to the most common questions, in plain language. Skim if you're in a hurry; dig deeper below.
Pay at most 70% of ARV minus rehab.
The 70% rule says your maximum offer should be (ARV x 0.70) - rehab budget. It bakes in a ~30% buffer to cover holding costs, financing, selling costs, and your profit. This calculator computes that ceiling for you in real time.
ARV - selling costs - total investment.
Net profit equals after-repair value minus selling costs (agent + closing, usually 6–8%) minus your total investment (purchase + rehab + holding + financing interest). The calculator above does this live as you change inputs.
Most flippers target 20% or higher on cash invested.
A healthy flip targets 20%+ cash-on-cash ROI on a 4–8 month hold. Anything under 15% leaves no margin for the surprises that always show up — overrun rehab, slow MLS comps, or extra months of holding costs.
Utilities, insurance, HOA, taxes, and loan interest.
Most first-time flippers forget that property taxes, vacant home insurance, utilities, HOA dues, and especially hard money interest keep ticking every single month you own the property. Six months of holding can easily eat $10K+ on a mid-priced flip.
The mechanics in short answers — no jargon, no upsell.
Find 3 to 5 recently sold homes within half a mile, similar size, age, and finish level. Your ARV is the median sale price of those comps — not the wishful highest one.
Walk the property with a contractor before you offer. Add 10 to 20% contingency on top of their bid. The most expensive surprises live behind walls and under floors.
Property taxes, vacant home insurance, utilities, HOA, lawn care, and loan interest — all of them accrue monthly. Multiply by realistic hold time, not your optimistic one.
Use (ARV x 0.70) - rehab as your hard cap on offer price. Going above it means you are accepting a thinner margin than experienced flippers in your market.
Designed so anyone can model their situation in under a minute, with or without a finance background.
Plug in purchase, rehab, ARV, and holding — get net profit and ROI without spreadsheet gymnastics.
Get the max offer price the 70% rule allows, recalculated every time you change ARV or rehab.
Run 10 deals in the time it used to take to run one — keep your buy box sharp at any market.
Models hard money or conventional financing interest over your expected holding period.
See ROI swing as you raise rehab — know which deals can absorb a contractor surprise.
A clean shareable card for your partner, lender, or agent without exposing your spreadsheet.
Everything you might ask before, during, or after using this tool.
ARV stands for After-Repair Value — the price your renovated property will sell for in current market conditions. It is the single most important number in a flip, and the easiest to overestimate. Pull it from sold comps in the last 90 days within half a mile of your subject property.
The 70% rule says your maximum allowable offer = (ARV x 0.70) - rehab budget. The 30% discount covers your holding costs, financing, selling costs, and target profit. In hot markets, many flippers stretch to 75%; in slow markets, disciplined investors stick at 70% or even 65%.
Most flips run 4 to 8 months end-to-end: 2 to 4 weeks to close, 8 to 16 weeks of rehab, 1 to 4 weeks on market, and 30 to 45 days to close the resale. Build your holding cost estimate around the longer end so a slow MLS does not destroy your margin.
Hard money is a short-term, asset-based loan from a private lender, designed for flips. Rates run 9 to 13% with 1 to 3 origination points. It closes fast and uses ARV as collateral, but the higher interest means holding costs add up quickly — model them carefully.
Plan for 6 to 8% of the sale price. That covers agent commission (typically 5 to 6% combined), title and escrow, transfer taxes, seller concessions, and the small closing fees that always sneak in. Setting selling cost % to 7% in the calculator is a safe default.
Cash-on-cash ROI = net profit divided by total cash you put in (down payment + rehab + holding + financing interest), expressed as a percentage. It tells you what your actual cash earned during the project — the metric most flippers and lenders actually care about.
If you are doing the work yourself, you can leave labor out of the cash budget but you should track the hours. A flip that looks profitable only because you worked 400 unpaid hours has a real ROI much closer to your local handyman wage. Be honest with yourself.
Add 10 to 20% on top of your contractor bid for surprises — old wiring, hidden water damage, code issues uncovered mid-permit. First-time flippers should add 20%; experienced flippers with a tight scope and trusted crew can run leaner.
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The 70% rule is a heuristic, not a law. (ARV x 0.70) - rehab gives you a maximum offer that leaves room for holding, financing, selling costs, and profit. In a hot seller market, sticking to 70% can mean losing every deal you bid on; in a cooling market, even 70% can be too aggressive.
Treat the rule as a default. If you have an unusually efficient crew, low financing cost, or a guaranteed buyer, you can ethically stretch above 70%. If you are new, or comps are thin, anchor at 65% and walk away from anything tighter.
Three rules: sold within 90 days, within half a mile, and within 10% on square footage. Photos matter — a comp that sold high because of a designer renovation does not justify your ARV unless your finish level matches.
When in doubt, take the median of 5 comps and shave another 3 to 5% as your underwriting ARV. The price you actually sell at is rarely your most optimistic comp.
Every extra month of holding is a tax bill, an insurance premium, a utility bill, an HOA payment, and — if you used financing — an interest payment. On a $300K project, 60 days of extra holding can vaporize $5,000 to $8,000 of profit.
Use a realistic timeline, not the one in your pitch deck. If the MLS is averaging 45 days on market in your area, plan for 60.
Three causes account for most overruns: hidden conditions (wiring, plumbing, foundation), scope creep (you decide mid-project to redo a bathroom), and code surprises (permits revealing required upgrades).
The cure is a thorough pre-purchase walkthrough with a contractor, a written and signed scope of work, and a 15% contingency you do not touch unless one of those three things hits.
Two short notes worth reading before you trust any number on this page.
Your loan amount, rate, and prepayment inputs never leave your device. No accounts, no cookies on your numbers, no analytics on the values you type. Disconnect from the internet and it still works.
We are not a bank, NBFC, advisor, broker, or distributor of any financial product. The numbers shown here are estimates for educational purposes only, based on the inputs you provide.
Results are not financial, legal, or tax advice. Please consult a qualified professional before any decision about your loan, investments, or personal finances. Actual loan terms and charges depend on your bank and individual circumstances.
