Separate price from assumptions
Compare cash price, financed price, dealer fees, equipment, roof work, storage, permitting, and ongoing service separately. A low monthly payment can hide a longer term or higher financed principal.
Treat savings as a scenario
Savings depend on electricity use, current and future utility rates, system production, export compensation, maintenance, financing, and tax eligibility. Ask for the spreadsheet assumptions behind any lifetime total.
Build a conservative comparison
Model more than one rate-escalation and production case. Confirm incentive eligibility with a qualified tax professional and current primary guidance rather than relying on a sales presentation.