What Is a Rent vs. Buy Calculator?
A rent vs. buy calculator is a comprehensive real estate decision tool that compares the long-term financial outcomes of buying a home versus renting and investing your capital elsewhere over a 30-year horizon.
Evaluating real estate decisions involves far more than comparing monthly rent checks to monthly mortgage payments. Homeownership includes upfront down payment commitments, closing costs, property taxes, homeowner's insurance, and ongoing maintenance expenses — offset by property equity growth and home appreciation. Renting, by contrast, frees up your initial down payment capital to earn investment returns in stocks, bonds, or index funds.
How the Rent vs. Buy Model Works
This calculator factors in all major cost drivers over a 30-year timeline:
By accounting for the opportunity cost of invested down payment capital at your target annual return rate (typically 7-8%), the calculator provides a mathematically rigorous financial recommendation.
How to Use This Calculator
- Input Home Buying Details: Enter the target purchase price, down payment amount, and mortgage interest rate.
- Input Renting & Investment Details: Enter your current monthly rent, expected annual rent inflation rate, and expected stock market investment return rate.
- Analyze Financial Recommendation: Review the clear 30-year summary identifying which option yields a higher net financial worth.
Worked Example
Consider a $450,000 home with $90,000 (20%) down payment at 6.5% interest vs renting at $2,400/month with 3.5% annual rent inflation and 7.0% investment returns:
1. 30-year total mortgage payments: ~$2,275/mo × 360 = $819,000.
2. 30-year maintenance & taxes (~1.5%/yr): $202,500.
3. Estimated home appreciation (3%/yr): $450,000 grows to $1,092,000 ($642,000 gain).
4. Net Buying Cost: $819,000 + $202,500 − $642,000 = $379,500.
5. 30-year total rent paid (3.5% inflation): $1,488,000.
6. Opportunity cost gain ($90,000 invested at 7% for 30 yrs): $90,000 grows to $685,000 ($595,000 gain).
7. Net Renting Cost: $1,488,000 − $595,000 = $893,000.
In this scenario, BUYING saves approximately $513,500 net over 30 years compared to renting.