Rooftop solar has moved from an environmental gesture to a straightforward financial decision for most commercial properties in North India. The evaluation, however, is frequently done poorly. Start with structural capacity. A rooftop solar installation adds roughly 12 to 15 kg per square metre. Older buildings, buildings with existing rooftop equipment, and buildings with waterproofing membranes nearing end of life require structural assessment before anything else. Retrofitting a roof under an installed array is expensive. Shadow analysis determines viable area far more than roof area does. Adjacent towers, water tanks, lift machine rooms, parapets and existing HVAC equipment cast shadows that vary by season. A proposal that quotes capacity based on gross roof area without a shadow study is quoting an aspiration. Understand the commercial model being offered. Under CAPEX, the building owns the system and takes the full benefit along with the full maintenance obligation. Under RESCO or OPEX, a developer installs and owns the system and sells power at an agreed tariff, typically on a 15 to 25 year agreement. CAPEX suits owners with capital and long horizons. RESCO suits those prioritising immediate savings without capital outlay. Net metering policy varies by state and changes periodically. The economics of a proposal are only as stable as the policy underlying them, so understand what happens to your returns if export compensation changes. Finally, maintenance is not optional. Soiling in NCR conditions can reduce output by 15 to 25% within weeks during dry months. A system without a cleaning schedule is a system quietly underperforming its projections.