What exists right now for someone who wants to make a very small solar project?

A family member of mine was hoping to put 1 or 2 panels on the roof of their ADU to power maybe just the small window air conditioner in it, or at least offset a lot of its energy use. Is there anything practical for doing this that doesn’t cost multiple thousands of dollars?

In my imagined setup, there would be 1-2 panels on the roof connected to a cheap consumer battery (something like a small ecoflow). The appliance would try and run only off the battery, but if the battery charge level dipped to low it would have some controller that would switch it to grid power until the charge level was back up. I would not want to feed any power into the grid, but I wouldn’t want the person living in the space to have to manually switch the power source between the battery and a regular outlet.