Mortgage vs Rent Lifetime Calculator

How the Buy vs Rent Math Really Works

Rent does not build equity — every dollar leaves permanently. Mortgage is part expense (interest, insurance, property tax) and part forced saving (principal payments build equity). Home value appreciation adds further wealth that renters don't capture. But buying has upfront costs (deposit, closing fees), ongoing costs (maintenance, property tax, insurance) and opportunity cost on the deposit that could have been invested otherwise. The long-run comparison requires modeling all these streams across decades.

What Tips the Balance

Low rent versus mortgage payment: renting wins short-term. High property appreciation: buying wins long-term. Short ownership periods (under 5-7 years): renting often wins due to transaction costs. Long ownership (20+ years): buying usually wins due to equity buildup and mortgage payoff. Rent inflation: high inflation favors buying since mortgage payments are fixed while rent grows. Low mortgage rates: buying wins. High rates: renting more competitive. The calculator handles all these variables.

Worked Example for Typical Decision

Property 300,000. Deposit 20% (60,000). Mortgage 5%, 25 years. Monthly rent 1,500. Compare 30 years. Appreciation 3%. Rent inflation 3%. Monthly mortgage approximately 1,403. Total mortgage paid over 30 years (25-year loan plus 5 years no payment) about 481,000 including deposit. Future home value 728,000. Net buy cost -247,000 (equity exceeds paid). Total rent over 30 years with inflation 855,000. Buying wins by approximately 1,102,000 under these assumptions. The number is large because of 30 years of rent inflation versus fixed mortgage payments plus equity appreciation.

What the Calculator Does Not Model

Maintenance costs (typically 1-2% of property value annually). Property taxes, insurance, HOA fees which rent typically includes. Transaction costs (Stamp Duty, closing fees, realtor fees) typically 3-8% of purchase. Opportunity cost of the deposit money (could have earned investment returns). Flexibility value of renting. Geographic variations in rent-to-buy ratios. Specific mortgage features (offset accounts, overpayments). The calculator shows core math; real decisions need adjustment for local conditions.

Patterns Commonly Observed in Buy vs Rent Comparison

Comparing monthly mortgage against monthly rent without accounting for the equity build (mortgage is partly saving). Ignoring maintenance and property costs that renters don't pay. Using current rent without inflating for 25-30 years of growth. Using optimistic property appreciation assumptions (historical average is 2-4% real). Forgetting opportunity cost on deposit. Assuming you'll stay in the home for 25+ years when most people move every 7-12 years. The calculator gives a principled comparison but real decisions involve many personal factors.