Who this comparison is for
Use this when you are choosing between two paths for the same stretch of years — staying a renter or buying a specific home — not when you are deciding whether a particular home is priced fairly. It is most useful once you have a real rent figure to compare, a purchase price you are actually considering, and a rough idea of how long you expect to stay, since the holding period changes the math more than almost any other input.
What each input means
- Years you expect to stay sets the holding period for both paths; a longer horizon generally helps the buy path recover its up-front costs.
- Purchase price, down payment, and up-front buying costs size the loan and the cash the buyer commits on day one — use your Cash to Close plan for the last one.
- Mortgage rate, loan term, property tax, insurance, HOA, and maintenance reserve build the buyer's annual ownership cost, the same categories used on the True Monthly Home Cost tool.
- Current monthly rent and annual rent growth project what the renter pays every year of the horizon.
- Annual home-value change and selling costs estimate what the buyer would net if the home were sold at the end of the horizon.
- Return on unspent purchase cash is what the renter's down payment and buying-cost cash could earn instead — the buyer's opportunity cost of that cash.
How the comparison works
For buying, the tool adds principal and interest, property tax, insurance, HOA, maintenance reserve, and up-front buying costs. At the end of each year, it subtracts estimated net sale proceeds after the remaining loan balance and the selling-cost percentage you entered.
For renting, it adds rent growing at your chosen annual rate. It then subtracts the assumed return on the cash you did not put into the purchase: the down payment and up-front buying costs.
What this does not know
- It cannot predict home prices, rent increases, mortgage rates, investment returns, local tax bills, repairs, insurance premiums, or your personal plans.
- It does not include income taxes, tax deductions, moving costs, utilities, renovation, PMI, special assessments, or differences in the homes themselves unless you adjust your inputs outside this simplified comparison.
- ”Break-even year” only means the first year in this scenario where the buyer’s modeled net cost is no greater than the renter’s. It is not advice to buy or sell.
A worked example, using the figures already loaded above
With every default value on this page left unchanged — a $400,000 home, 15% down, a 6.5% rate, $2,200 rent growing 3% a year, and a 7-year horizon — the estimated home value after 7 years is about $491,950, against a remaining loan near $307,415, for roughly $184,500 of buyer equity before selling costs. The model’s buyer net cost at year 7 comes to about $115,000, versus an estimated $174,200 for the renter, a gap of roughly $59,000 in this scenario. Because the assumed 3% annual appreciation on the full home price outpaces the 7% one-time selling cost fairly quickly here, this particular set of assumptions shows buying ahead for every year of the horizon, not just year 7 — that is a property of these specific numbers, not a rule. Change the appreciation, rent growth, or investment-return assumption and the crossover point moves or disappears.
How to interpret the result
Read the headline difference together with the break-even year and the chart, not by itself. A small dollar difference at a short horizon is less decisive than the same difference at year 15, because more of the buy path’s advantage in this model comes from years of compounding appreciation and equity paydown. If the two lines in the chart stay close for most of the horizon, the decision is more sensitive to your assumptions than the single headline number suggests — try raising rent growth, lowering appreciation, or raising the investment-return rate to see how much the answer moves.
Common mistakes
- Using a home-appreciation rate you would not also expect from rents in the same market, when the two tend to move together over long periods.
- Comparing rent for a smaller or lower-amenity unit against the cost of the exact home you would buy.
- Ignoring the “up-front buying costs” field, which understates the buyer’s real starting cash outlay.
- Treating the break-even year as investment advice rather than as one output of the specific assumptions entered.
Related guides and calculators
- Rent vs. buy assumptions guide — a deeper look at each assumption this tool asks you to set.
- True Monthly Home Cost calculator — the buyer’s monthly payment behind this comparison, broken out in full.
- Move-In Reserve calculator — the short-term cash both paths require at the moment you move.
- Maintenance Reserve calculator — replace the flat maintenance percentage used here with a more detailed plan.
Sources and safe next steps
The fixed-rate loan payment and remaining-balance calculations use standard amortization mathematics. No local costs are automatically estimated. Use your Cash to Close plan, lender documents, insurer quote, HOA documents, and actual comparable rent to replace the example inputs. See the site methodology and limitations.