Calculator
Real Estate Flip Profit Calculator
Real Estate Flip Profit Calculator
Agent + closing + staging + repairs before sale
The 70% rule says a flipper should pay no more than 70% of the after-repair value minus renovation costs. Use this calculator to test whether your numbers clear that bar before making an offer. The "Selling Cost %" slider captures agent commissions (5-6%), transfer taxes, and any pre-sale touch-ups.
Net Flip Profit
$21,450
ROI
5.7%
Annualized
11.5%
The flip nets $21,450 on $403,550 total — a modest 5.7% ROI (11.5% annualized). Thin margins mean any overrun in reno or selling costs pushes the deal negative. You earn about $3,575 per month of holding time. Consider negotiating buying costs or adding value to the property to widen the spread.
*Excludes capital gains tax and GST considerations and assumes costs as entered; actual projects often overrun budget. Educational only, not investment advice.
The Math Behind Every Successful Renovate-and-Sell
A property flip is a simple trade in principle — buy below value, add value through renovation, sell above cost — and an unforgiving trade in practice, because the profit lives entirely in the gap between a handful of estimates. Every input is a guess: what the property is worth after repairs, what the repairs will actually cost, how long the hold will really take, and what the market will pay on the day it settles. The margin between those guesses is the business, and the most common failure mode is not bad luck but arithmetic done loosely at the start, then discovered precisely at the end. Australian flippers face a few local twists worth pricing honestly: agent commissions here run lower than US norms but conveyancing, transfer duty on the buy and marketing budgets still consume real money; renovation labour is scarce and quoted months out; and profit from a deliberate resale is generally taxed as income without the 50% CGT discount — the ATO looks hard at renovate-and-sell patterns. This calculator operationalises the full economics behind the classic heuristic: purchase price, renovation budget, financing costs, monthly carry during the hold, total selling costs and target sale price. It prints the net profit, return on total invested capital, the annualised return that makes flips comparable across hold periods, and profit per holding month — the number that reveals whether a deal is earning its time.
Every Cost Counts Twice: Once Now, Once at Sale
The total cost of a flip is the sum of everything spent to acquire, renovate, carry and sell: purchase price plus renovation budget plus financing costs plus months times monthly carry plus selling costs as a percentage of the sale price. Profit is simply the sale price minus that total, and the arithmetic is unforgiving because every cost item is inescapable — a cost forgotten in the analysis does not disappear when the deal closes; it arrives on the settlement statement. The monthly carry deserves emphasis: interest on the borrowed money, rates, insurance and maintenance running every month of the hold, and a hold that stretches from six months to nine quietly adds three months of that burn to the cost basis. The deals that lose money most often lose it here — not in the purchase or the sale, but in the months the project took longer than planned. The two return figures answer different questions. ROI on total cost divides profit by all money that went into the deal; annualised ROI converts that to a yearly rate by multiplying by twelve over the hold months — the only honest way to compare a six-month flip against a three-month one, since a 20% gain over three months is a very different business than a 20% gain over twelve. The third reading — profit per month of hold — catches bad deal structure: a flip that earns $30,000 over nine months produces about $3,300 a month before tax, and the question that number raises is whether your capital and your months are working hard enough.
Expert Insights
Run the Numbers Three Times Before the Offer
Professional renovators price a deal with three sets of assumptions: the plan case, the likely case with renovation costs inflated fifteen to twenty percent and the sale price pulled down five percent, and the bad case with both moved against them. The offer should clear a reasonable return in the likely case, because the plan case is the marketing and the bad case is the tail risk. Run the inputs three times here, and any deal that only pencils on the optimistic numbers is a gamble priced as an investment.
Selling Costs Still Add Up Despite Cheaper Commissions
Australian seller-side costs are leaner than American ones — many vendors negotiate packages near two percent including marketing — but they are not zero, and budget sellers forget staging, styling, photography and the pre-sale touch-ups that decide the campaign. On an $820,000 sale even 2.5% is a $20,500 line item. Enter a quote-based percentage for your specific market rather than a round number picked because the deal needed the margin.
The Taxman Treats Flips as Income
A property bought to resell at a profit is generally accounted for as trading stock or ordinary business income: no 50% CGT discount, and possibly GST consequences if you substantially renovate new-ish property. That can push the effective tax on flip profits toward the top marginal rate. Reserve roughly a third to half of projected profit for tax before deciding whether the annualised return clears your floor — the after-tax number funds the decision, never the gross one.
Actionable Tips
- 1
Back Into Your Maximum Offer Price
Set a minimum acceptable annualised return, hold the renovation and carrying estimates at realistic values, and let the calculator find the highest purchase price that still clears the return. That number is your auction ceiling — bid from it, not from what the vendor asks. Most first-time renovators do the reverse: start from the asking price and hope the sale covers the costs.
- 2
Budget With Trade Quotes, Not Percentages
A renovation estimate expressed as a percentage of the purchase price is a guess wearing a number's clothes; a budget built from itemised quotes is arithmetic. Get at least two written quotes before finalising the analysis and add fifteen percent for overruns. A $15,000 overrun on a $610,000 project is several points of annualised return — the input deserves the accuracy it will demand when it is real money.
- 3
Treat the Hold Period as a Budget, Not a Hope
Set the holding period from the renovation timeline plus a realistic four-to-six-week campaign and thirty-to-sixty-day settlement, then add buffer. Every extra month adds the monthly carry to cost and dilutes the annualised return simultaneously. If the deal needs nine months to clear a reasonable return, a smaller scope with a faster cycle is often the better use of the same capital.
Real-World Examples
Jordan Walked Away From the Spread
Jordan eyed a weatherboard listed at $650,000 with a projected post-reno value of $825,000 and a $70,000 renovation scope. The gross spread looked like $105,000, but the full cost stack — nine months of carry at $3,400, finance costs and selling fees — left under $18,000 net, an annualised return below his term deposit. He bid to his number, was refused, and walked. The property later sold with a reported renovation blowout; the thin margin had told the truth about its risk first.
Priya Found Her True Cost of a Slow Tradie
Priya's four-month plan stretched to seven waiting on waterproofing and tiling trades. The extra carry added over $6,000, and her profit-per-month readout slid as the calendar did. Seeing the arithmetic mid-project changed decisions: she paid a premium to parallelise painting with flooring and listed two weeks early. The premium cost less than the carry it saved — trade-offs the calculator made visible while there was still time to spend them.
Tom's Velocity Lesson
Tom tied up capital for eleven months in one large house flip returning 14% annualised while passing on two smaller unit refreshes each returning 22% annualised over four months, because the bigger cheque felt more substantial. Two turns at 22% outproduced one long hold by a wide margin across the same year. From then on he priced every deal by annualised return and hold months; the scoreboard is velocity, not cheque size.
Glossary of Terms
- After-Renovation Value (ARV)
- The property's estimated market value once works are complete — the anchor number behind every flip margin calculation.
- Carrying Costs
- Interest, council rates, insurance and maintenance paid each month of ownership during the renovation and sale period — the cost of time.
- Profit Per Month
- Net profit divided by holding months — the readout that exposes deals earning less than your time and capital are worth.
Frequently Asked Questions
Everything you need to know about this topic.
Ivy Sinclair-Wren
Financial Chaos Analyst
Ivy Sinclair-Wren is a Financial Chaos Analyst covering investing, AI, wealth psychology, and the emotional consequences of opening finance apps during market crashes. Based in Melbourne, she specializes in demystifying the Australian tax code and helping users navigate the intersection of spreadsheet logic and human irrationality.