About the uncertainty analysis
The charts and table above summarize 10,000 simulations — but it can be useful to see what individual futures actually look like. Each line below is one possible path. The wide spread isn't a flaw in the model; it's the honest shape of uncertainty. These charts are less about drawing conclusions and more about building intuition for how much luck — good or bad — can shape the outcome.
Buyer — 20 random paths + baseline
Run simulation to see paths
Renter — 20 random paths + baseline
Run simulation to see paths
The chart below compresses all 10,000 simulations into percentile bands. Where the green and blue regions overlap is the zone of genuine ambiguity — futures where either choice could come out ahead.
Percentile bands — Buy vs. Rent (10th / 25th / median / 75th / 90th)
Run simulation to see percentile bands
Why does the chart look the way it does?
Both the buyer and the renter tend to build wealth over time — the buyer's net wealth grows with the housing market, while the renter's grows with their investment returns. But the path each takes, and why one often pulls ahead of the other, comes down to a few key forces worth understanding.
The buyer starts in a hole. Buying a home comes with significant upfront costs — closing costs, inspections, moving costs — that you never get back. And when you eventually sell, there are more non-recoverable costs: agent commissions, transfer taxes, and closing fees on the way out. In the early years, the buyer is essentially paying off that deficit before they can start pulling ahead.
Over time, the buyer's position strengthens in one powerful way. Each mortgage payment builds a little equity — you're slowly paying yourself back. And your fixed mortgage payment becomes comparatively cheaper as rents rise with inflation. But the biggest factor is leverage. When you buy a $500,000 home with $100,000 down, you're not just earning appreciation on your $100,000 — you're earning it on the full $500,000. If the home goes up 5%, you've made $25,000 on a $100,000 investment. That's a 25% return. Put that same $100,000 in the stock market and earn 10%, and you've made $10,000. The math of leverage is powerful — but it cuts both ways. A 10% drop in the housing market doesn't cost you 10% of your investment; it can cost you more than you put in. Ask anyone who bought in 2006.
The renter's advantage is speed and flexibility. No closing costs, no down payment tied up, no selling fees. The renter's money can go straight to work in the market from day one. And historically, the stock market has outpaced home appreciation over long periods — which is why the investment return assumption in this model has such an outsized effect on the outcome. If the renter actually invests that money, and markets cooperate, renting can be the better financial decision even without the leverage advantage of owning.
The bottom line: buying is a leveraged bet on your local real estate market. Renting is a bet that liquid investments will outperform. Neither is obviously right — which is exactly why this tool exists.