after that you'd have to be some nightmare of a clutz to permanently mess up your guitar. ;)
as for me I'm so cheap that the thought of getting anything done to my guitar professionally never came up until I bought EMG pickups for my Axe and even now. I know that next time I get new pickups for a new guitar I'm doing it myself because I can simply look at one of my guitars and use it as a reference. (one has passives and one has EMG's)
It's just a better feeling knowing your not gonna get ripped off.
I learned my lesson by paying a sick total of $350 Canadian plus my old beginner electric trade in and my passive emg's that were being replaced. All this just for 2 active EMG's, never again will I be raped like that.
another thing never trade in just sell your stuff yourself you will get at least double what the store will offer.
" "this tone ain't workin for me" is the first thing a guitar player says when he hasn't done his homework"- Bob Rock