Better quotes start with a better brief.Compare the scope—not only the price at the bottom.
Prepare a consistent project brief, compare solar quotes and evaluate installers on scope, assumptions, support and workmanship—not price alone.
Give every installer the same starting information.
Energy
Monthly/daily kWh, outage pattern and which loads are critical.
Site
Roof or land, building type, existing electrical equipment and access.
Goal
Bill reduction, backup, off-grid operation, generator displacement or a mix.
Constraints
Budget range, timeline, future loads and any equipment already owned.
A cheap quote can be a smaller scope wearing the same system-size label.
Ask for exact models and written assumptions. “8 kW system” is not enough information to compare two proposals.
| Line item | Installer A | Installer B | What to ask |
|---|---|---|---|
| PV modules | Exact model? | Exact model? | Quantity, wattage, warranty, layout |
| Inverter | Exact model? | Exact model? | Architecture, MPPT, backup output |
| Battery | Usable kWh? | Usable kWh? | Power, warranty, compatibility |
| Protection & mounting | Included? | Included? | Ask for scope and exclusions |
| Support | Response path? | Response path? | Workmanship warranty, monitoring, service |
Slow down if the proposal avoids specifics.
- No exact equipment model numbers
- Battery quoted only in Ah without system voltage/usable kWh
- Production or savings promise with no assumptions
- Warranty language that never says who supports the claim
- Pressure to pay before the scope is documented
- No commissioning or monitoring plan
A better installer search starts before the first sales call
Give every installer the same project brief. That reduces the chance that one quote includes battery backup, electrical work and protection while another appears cheaper because those items are missing.
Your project brief should include
- Property location and property type
- Recent electricity use or bill information
- Critical loads
- Backup duration target
- Known roof/site constraints
- Existing generator, UPS or solar equipment
- Budget range if you have one
- Desired project timeline
Compare the proposals line by line
| Area | What to compare |
|---|---|
| Equipment | Exact models, not “Tier 1 panels” or “10 kWh lithium battery” |
| Scope | Mounting, protection, cabling, distribution changes, monitoring, permits |
| Performance | Production assumptions, backup limits, excluded loads |
| Warranty | Product warranty, workmanship, response process, local support |
| Commercial | Payment schedule, change-order process, taxes, exclusions |
Red flags
- Refusing to name the exact equipment before payment
- Guaranteed savings without showing assumptions
- No explanation of backup-load limits
- No documentation or commissioning handover
- Pressure to pay immediately because a “deal ends today”
Primary sources and further reading
Melnti uses primary or institutional sources where they are available. Always confirm current rules, tariffs and equipment documentation before purchasing.