Solar in Alabama has to live on a roof that also takes hail, pine shade, and Gulf wind. The first subject is the deck and the surface under the rails, not a brochure sky. A bruised shingle field, a soft deck, or a porch roof with almost no slope will fight any array you set on it.
Pines and water oaks break the southern exposure on older lots. A roof split into many small planes by dormers leaves little clean area. Ridge houses get more open sky and more wind. Valley houses sit in tree tunnels. Coastal sites take uplift that inland prairie roofs feel as hail instead. Say which of those is your actual roof, and what the attic wood looks like.
Penetrations are leaks waiting for a sideways rain. Flashings, boots, and rail feet have to shed water the way the rest of the roof does. Skip sheathing on a bungalow may not hold a mount the way a later plywood deck will. An inverter in a hot attic or a closed garage cooks itself in an Alabama July. The electrical panel in an old mill house is often crowded before any new circuit is discussed.
Hail country from the Tennessee Valley through the middle of the state can pit glass and bruise the shingles around the array. If the roof is already near the end of its life, mounting hardware on it borrows trouble. Wind on the Fort Morgan side of the state and on open Black Belt ridges pulls at edges. Ask about attachment and about the condition of the felt you cannot see from the yard.
Call with the roof type, the shade, and the direction the main slope faces. Mention dormers, skylights, and a porch that ties in low. Say whether the attic shows rotten decking or daylight. This conversation is about whether the house can carry the equipment in this weather. Leave the sales math alone and describe the roof you actually have. Call the number on this page.