Rent vs. Buy Financial Analyzer
| Metric | Alex (Buyer) | Troy (Renter) | Winner |
|---|
Rows = Investment Return Rate | Columns = Home Appreciation Rate | ★ = Your current assumptions
Rows = Mortgage Rate | Columns = Holding Period (Years) | ★ = Your current assumptions | All other inputs held constant
Rows = Investment Return Rate | Columns = Down Payment % | ★ = Your current assumptions | All other inputs held constant
5–10 years → Neutral Outcome depends on market conditions and requires a detailed analysis.
10–15 years → Slight edge to buying Still requires a detailed analysis to confirm.
15+ years → Owning usually wins Equity accumulation and appreciation begin to decisively outpace rent savings.
15–25× → Analyze carefully Neither option has a clear advantage — local conditions and your situation determine the outcome.
> 25× → Rent Buying is expensive relative to renting. High-cost markets like San Francisco (31×) and NYC (22×) fall here.
Troy spends savings → Buyer wins by $200K+ If the renter spends rather than invests, homeownership wins decisively. Forced equity is a powerful wealth-building mechanism for those without investment discipline.
Historically, stocks have won Over most 10-year windows, S&P 500 returns have outpaced home appreciation — giving the disciplined renter the edge in 32 out of 36 modeled scenarios.
High appreciation flips the result At 6%+ annual home appreciation with investment returns at 7% or below, buying outperforms. Use the Sensitivity Matrix tab to model your specific assumptions.
Mortgage interest deduction Available on loans up to $750K, but post-TCJA many Midwest homeowners no longer benefit from itemizing — the $29,200 married standard deduction often exceeds total itemized deductions.
SALT cap Property tax deductions are capped at $10,000/year under the 2017 Tax Cuts & Jobs Act.
① Calculation Method — Pure Cash Flow
This calculator uses a pure cash flow method rather than the presentation's
8-step subtraction approach.
Alex's net worth = sale proceeds − remaining mortgage − closing costs + tax savings.
This is simply what Alex walks away with after selling. No further adjustments needed —
Alex's equity already reflects every dollar she spent on the home through mortgage amortization.
Troy's portfolio = initial $115K compounded + actual monthly cash savings invested.
Troy genuinely saved the full difference between Alex's total monthly outflow and Troy's rent —
including the principal portion — and invested it every month.
The presentation's Step 6 subtraction (cumulative extra costs) is not applied here because
it creates a double count: principal is simultaneously credited to Troy's portfolio as investable
savings and subtracted from Alex's net worth as a penalty — even though Alex received
that same principal back as equity. The pure cash flow method eliminates this by keeping
Alex's equity and Troy's portfolio as two fully independent, accurate calculations.
② Tax Savings — TCJA (2017) Applied
The companion presentation (Slide 7) shows $55,764 in tax savings,
calculated using pre-TCJA full itemization — mortgage interest plus property taxes multiplied
by the marginal tax rate, with no limits applied.
This calculator applies correct post-TCJA (2017) law: property tax
deductions are capped at $10,000/year (SALT cap), and the homeowner only receives a tax
benefit on the amount by which itemized deductions exceed the standard deduction
for their filing status (user-adjustable).
For a married Midwest homeowner at the base case assumptions, itemized deductions
do not exceed the $29,200 standard deduction — producing $0 in incremental
tax benefit. This is consistent with the presentation's own Slide 7 footnote, which
states that many Midwest homeowners no longer benefit from itemizing post-TCJA.