
This charger is inside the engine compartment. It rides there all the time. The power cord is fed through the doghouse inside. If I need to charge this faster than the onboard setup I simply plug it in when connected to shore power.
Some folks will go nuts on this sort of thing but when you drive a '94 you mustn't be so tender (see what I did there?).
As for solar ... there is so much out there in the used market that putting something together is quite simple. Just be mindful of where you tap into your wiring. We went with a 750w set up (3 panels on the roof) but we are in here full time. My neighbor has a 55w panel and a cheap charge controller he just sold for $50 (our set up was quite a bit more but everything but the 5 batteries were purchased used).
Keep your eyes open.