Solar in Hawaii sits in strong sun, salt air, and trade winds, on metal roofs and low-slope roofs that may already be tired. The questions that matter are whether the roof can carry the array, who owns the panels, and who gets called when an inverter goes quiet. A clear afternoon is not a scope. Uplift and corrosion are. Do not arrive with a speech about anything other than the roof, the hardware, and that call.
Do not put rails on rusted fasteners, a soft deck, or wood the termites have thinned. A low-slope roof holds water at a hole that a steep roof would shed, and salt makes that hole a corrosion problem as well as a leak. Ask how the feet are flashed and what happens when the covering is replaced. An ohana roof and the main roof are different structures. Say which one you mean.
Ask who owns the panels before anyone talks about touching them. That answer is also who you call when the inverter goes quiet. Name the modules and the inverter, and put the gear where salt can be seen and a person can reach it. Do not stick it in a closed room that already traps heat because the breeze was blocked. Shade from a tree still counts on a bright day.
Finish a tired covering before rails go down. Rust and an active leak are not a base for an array. The electrical service in an older single-wall house may be modest, and a newer house or an ohana may already be full. Someone has to look. Trade winds are an uplift problem for the mounts on ordinary days, not only on the windiest day. Say what the service looks like now.
Say the town, metal or low-slope, and whether rust, termites, or a leak is already on that roof. Say who owns the panels if you know. If you do not know who to call when the inverter goes quiet, say that too. A tired covering comes first. Call the number on this page.