The 40-30-30 Affordability Rule
A home loan EMI should not exceed 40% of your net monthly income. Total liabilities (home loan + car loan + personal loan) should not exceed 50%. After all EMIs and basic expenses, you must have at least 20% leftover for SIPs, emergencies, and lifestyle. If your home loan EMI alone is 50%+ of income, you have bought a house you cannot afford — even if banks approved the loan. Banks approve up to 60% EMI burden, which leaves you house-poor. Always self-restrain to 40%.
The Hidden Costs of "Affordable" Homes
A ₹50 lakh home does not cost ₹50 lakhs. Add 5-7% stamp duty (₹2.5-3.5 lakhs), 1% registration (₹50,000), 1-2% loan processing (₹50,000-1 lakh), 1-2% interior costs (₹1-2 lakhs), advance maintenance and society deposits (₹50,000-1 lakh), and miscellaneous expenses. True total: ₹54-58 lakhs. Plan for the full 10-15% buffer above sticker price. The buyers who underestimate end up paying these costs from credit cards or personal loans, dramatically increasing their effective interest burden.
Tenure Decisions: Why 20 Years is the Sweet Spot
Banks offer up to 30-year home loan tenures. Sounds great — lower EMI! Reality: 30-year loans cost 50-70% more in total interest than 20-year loans. The "EMI savings" is illusory because you pay it back many times over in extended interest. A ₹50 lakh loan at 8.5%: 20-year EMI is ₹43,391 (total interest ₹54 lakhs). 30-year EMI is ₹38,446 (total interest ₹88 lakhs). Saving ₹5,000 monthly costs you ₹34 lakhs extra. Choose 15-20 year tenure unless absolutely necessary.
Prepayment Strategy That Saves Lakhs
Every prepayment in the early years of a home loan saves disproportionately more interest than later years. Here is the highest-impact strategy: in years 1-5, use bonuses and surplus to make principal-only prepayments of ₹1-2 lakhs annually. A ₹1 lakh prepayment in year 2 saves ~₹1.5 lakhs in total interest. In year 15, the same ₹1 lakh prepayment saves only ₹15,000. Always prioritize early prepayments. For floating rate loans (most home loans now), there are zero prepayment penalties.