I currently have three solar power systems in operation at the house.
The first is my original Harbor Freight 45W kit panels, they don't produce a whole lot but are plenty for charging small batteries or portable use with small items.
The second system is a single-panel 135W system for my ham radio bench, wired to an off-grid 12V 100AH AGM battery under the bench. I normally only use it for the ham gear, but do have a couple 12V inverters I can connect for AC power if needed in a pinch - sort of a backup to the backup!
My main system consists of eight 135W panels wired to an Outback Power charge controller. I have a full set of Outback gear comprising my 48V 220AH home backup system. I feed a dedicated subpanel which supplies outlets in various parts of the house. In a pinch it can run the fridge or even gas furnace, but most of the time just keeps my home network going.