Start with legal and technical eligibility
A good price is not enough. Check whether the installer has the licences, certifications, insurance and electrical capability required for the work in your location, and verify the applicable local licensing rules rather than assuming one credential works everywhere. The exact requirements vary by country, state and municipality. For battery storage, backup, three-phase systems, EV charging or generator integration, ask whether the business has actually completed that type of project before.
Compare evidence, not just marketing
Ask about relevant completed-project experience: how many similar systems the installer has completed, which equipment families they regularly commission, who performs the electrical work and whether subcontractors are used. Melnti separates business checking, capability-fit matching and verified Melnti project history because those signals answer different questions.
Read the proposal line by line
- Exact panel, inverter, battery and control-equipment models
- PV DC size and inverter AC output
- Usable battery capacity and continuous/peak power
- Roof/mounting scope and electrical-board changes
- Monitoring, commissioning and customer account access
- Permits, utility/grid applications and inspection responsibilities
- Product warranty and installer workmanship warranty
- Payment milestones and cancellation terms
Do not treat every non-completed quote as installer failure
Projects can stop because a customer changes plans, financing fails, a roof is unsuitable, a utility refuses a configuration or the installer finds a safety problem during site assessment. A useful reputation system separates those reasons instead of publishing a crude failure number.
Use verified customer evidence where possible
Melnti counts a verified completed project only after a tracked project reaches completion and the customer confirms the outcome. Verified-project reviews are shown separately from general comments. This does not guarantee future workmanship, but it creates a more useful evidence trail than self-reported installation counts.