Fix and Flip Calculator
On a flip the purchase price is the answer, not the question. Begin at the resale figure and work backward.
What This Calculator Does
Your after-repair value goes in first, and from it the calculator subtracts the rehab budget, financing and holding costs, and the cost of selling — leaving projected profit, margin, and the highest purchase price those numbers can justify.
Who Is This For
Made for investors underwriting a renovation project, contractors moving from building for others to buying their own, and anyone evaluating a distressed listing who wants a disciplined number rather than an optimistic one.
How It Works
Enter a realistic after-repair value drawn from comparable sales, your rehab budget, the expected holding period, and your financing, carrying, and selling costs. The calculator returns projected profit, margin, and the ceiling price that still meets your target.
Frequently Asked Questions
How useful is the 70% rule?
It works as a screening shortcut: pay no more than 70% of after-repair value minus the rehab budget. That helps decide which listings deserve a second look, and it is not underwriting. Once a deal is live, replace it with your actual costs — the rule quietly assumes a margin and a cost load that may not fit your project.
Which costs get overlooked?
Holding costs while the work runs — loan interest, taxes, insurance, utilities, association dues — together with the cost of selling: commission, documentary stamps, and title. Between them they routinely consume the profit that a purchase-plus-rehab estimate appeared to show.
Do flips work in Miami?
Selectively. Miami behaves more as a condo and appreciation market than a value-add renovation market, and association rules and approval processes restrict what can be done inside a unit. Flips here cluster in particular single-family pockets where the housing stock is dated and the land holds the value.
Where should the after-repair value come from?
From closed sales of comparable, similarly renovated properties in the same neighborhood — not from active listings, and not from what you hope the market will do. If the after-repair value requires the market to rise before the numbers work, you are placing a bet on timing rather than running a renovation project.
How are flips financed?
Typically with short-term investor debt priced well above a conventional mortgage, frequently with points at origination and interest-only payments during the hold. With benchmark 30-year rates near 6.6-6.7% in mid-2026, flip financing sits meaningfully higher, and every additional week on site costs real money.
What margin is enough?
Enough to absorb a rehab overrun and a slower sale than planned, since both occur often. Model a longer hold and a lower resale price alongside your base case. Where the deal only works in the optimistic column, it is not a deal.