A home appreciating in value looks great — but you're also paying mortgage interest, property levy, insurance, and maintenance. Net Value captures the full picture:

For Buy, what you'd walk away with is the sale price minus the remaining mortgage, selling costs and any capital-gains tax, plus what the buyer invested along the way, including any tax savings from deducting mortgage interest and levies. For Rent, it is your investment portfolio after capital-gains tax.

Everything you paid in is the same total for both: the up-front costs, plus each month the larger of the rent and the cost of owning, because the cheaper side invests the difference. So both numbers are often below zero.

This tells you which strategy actually leaves you wealthier. A scenario can have higher asset growth but lower net value if the costs are steep enough.

The breakeven point is the year when buying overtakes renting + investing in net value. Before this point, the renter is wealthier. After it, the buyer pulls ahead.

No breakeven? That means one strategy dominates for the entire simulation period. If you're planning to sell before the breakeven year, the dominant strategy may flip.

The main charts assume growth rates play out exactly as configured. But nobody can predict 30 years of returns. The How sure is this? section runs hundreds of simulations where property appreciation, equity growth, and rent inflation vary randomly each year using bell-curve distributions centered on your inputs.

Instead of “Buy wins by $142K,” you see: “Buying wins in 68% of simulations.” The fan chart shows the range of possible outcomes, and the What could change the answer? chart shows which single assumption could flip the verdict.