Yes DC means 12-18v in most cases so car battery territory, leisure batteries are just like our lipo's you have to have the right size and look after it. Piece of string for how many charges. (Charge at home then top up, I have fully charged 5 x 5300 packs from a 85AH battery before noticing the input was down to 11v.)
I have now 2 old 5300 turnigy nano techs that will run 2 boosted carpet heats just!! but would only manage 1 heat on big asphalt tracks, I would not only look at 1 lipo so you can have 1 topping up as the other cools.
Used electrics is fine, most sellers on here are seasoned racers so upgrading and not selling off damaged gear but note I did say most
