Greetings and advice on a used GEM

Hi Everyone, I am new here and new to GEM cars in general. I will be turning a GEM into a Camera Car and hoping to get some advice on them.
Found a 2007 EL XD for sale and curious if there is anything that I should be looking out for when buying a used GEM? It will have new flooded batts when I buy it.
How long do the Motors last normally?
Any tips on how to improve power/ quickness?
Thanks, J