DOOF,Hi, Just like so many members of this Forum we once shared with you the Tank building skills of a dead hedgehog BUT the old cliché about practice making perfect is true.
Start simple and gently progress, why in 25 years and about £250,000 and a couple of divorces you too will be an expert

It is not my place to tell you what to start with but if you are truly butterfingered it might be best to start with a Tank that is inherently larger than most others in the same scale so that you can actually get yourself hands on without fear of disaster,
Perhaps a1/16 r/c HENG LONG or TAIGEN Tiger 1 which with smoke and sound and an RX18 control board, I would not expect you to pay more than £80 to £120.
You must encourage your son to take an active part in any build if only so that you have someone to blame.
REMEMBER that when it does go unerringly straight towards the nearest cliff the Forum has already been there and we WILL help, you just have to ask,
TANKMAN's advise about Dave at FORGEBEAR is 100%, one of the gold plated dealers in our hobby, He can be found on E-BAY and at www.
theallertons@fsmail.net you could also look at Steve's site at
http://www.welshdragonmodels.com, another hero who like Dave will look after you.
AND try to remember at 2 o clock in the morning when the upgrade that cost you an arm and a leg just does not fit you are doing this for fun

shaun