Solar in Hartford starts on an older roof that may not be ready to hold anything. Soft decks, several eras of patch, slate on a West End house, and shade from the next three-family are the first facts. Streets are tight. A slope that is bright at noon can be dark by midafternoon because of a taller block or a mature tree. Flat porch roofs and pitched main roofs do not take the same mount. Say which one you mean.
Fix the roof before anyone fastens to it. A ponding porch roof or a chimney with bad flashing will leak around new holes faster than the old field ever did. Snow slides off a smooth surface onto the lower roof and the entry. Hardware has to live with that, and with wind down the river valley. None of this is a forecast of output, and it should not be told as one.
Brick houses with old electrical service often have a full panel in a damp basement. A meter location, a crowded cellar wall, and wiring that was never cleaned up all change the job. Visible fronts on older streets raise the question of what faces the sidewalk. Drilling slate is a serious alteration. Access without a driveway means the materials come through the building or up from a narrow yard.
Shade you refuse to cut, or a tree the block will not lose, belongs in the first call. So does a roof that already needs to be replaced. Ask how each attachment will be flashed, and how a later leak at that hole gets closed without destroying the field. A finished top floor under the rafters changes how the work is walked and wired. Mention it.
Call with the neighborhood, the roof material, and what shades the slope. Mention slate, a soft deck, or a porch roof if that is the surface. Ask about structure and flashing. Nobody on the phone should promise what the equipment will produce. Call the number on this page.