I've found that by using Lithium batteries, they last years. I also keep an assortment of batteries in my camper for 'emergencies'.
I don't have photos of my install, I just got the parts yesterday. But I will take some photos while I do the work. Hopefully today!
Basically, there is a compressor, a manifold and a relay with some wires to connect them.
Here is a photo of an installation and like how I will try to do mine;
The guy used a plastic tool box to mount the equipment in. There is a hole for the power wire and two holes for the two air lines running to each air bag. The parts are mounted in the tool box lid, so they flip down for service, then back up when stowed.
test