Words of wisdom from YHR - one further point which I regard as really important and has tripped me up on a few occasions is the build consistency of HL tanks. I have bought a Leo 2A6 and a King Tiger recently and both have the 8 pin connector which drives the turret functions wired back to front. This isn't a problem if the tank works okay, but when you come to troubleshoot and/or upgrade to a Clark board etc. then it can be really confusing as the colour coding of wires is reversed. Not a massive deal but to a newbie, I can imagine it causing all sorts of trouble and frustration. Also, some skill in soldering - particularly light AWG wires would be helpful and you will need to be able to read a basic circuit diagram.
Best of luck old chap!!
cheers
CaptB