Stop relying on “brochure maths”. Our metric sheet forces you to punch in gross yield, net yield, price-to-rent ratio, IRR, break-even month, maintenance leakage, vacancy probability & exit cap-rate before you sign that flat agreement. We explain formulas, acceptable benchmarks for Navi Mumbai (net yield >4%, break-even <96 months) and red-flag thresholds. Live example: 2 BHK in Ulwe—headline 5.2% yield shrinks to 3.9% after CAM & tax, break-even 108 months—deal rejected. Spreadsheet auto-flags risk. Keywords: property investment metrics, rental yield calculator, buy-to-let checklist.