New LS1 Owners - Newbie Tech - What should I look for? Buying help...

I've seen a decent number of LS1 F-Bodies in solid cosmetic shape and claimed solid mechanical shape. I was wondering if there is anything in particular to look out for or if it was basically a crap shoot when buying one of these? For example, I found a VERY nice 1998 z/28 A4 Vert with 110,000 miles on it. Good condition inside and out, but I worry about things like the transmission, rear end, engine etc. I don't care too much about small stupid things but I don't want to buy a car thinking it's in good running order and then my rear end, transmission or engine shits the bed...

What are the important things to consider? The expensive stuff that breaks and is common with these cars and what are the things that don't usually cause concern as long as the car hasn't been owned by a moron?

Rear end: I know the 10 bolt is a weak point of this car, how do you tell if it's on its way out? What are signs? How much is it to fix when and if it does and how often does it happen? What's the solution and how cost?

Transmission: How strong are the A4's and the M6's... when do they crap out and what mod load can they take? When should one expect to do this or that, repair, rebuild etc and how much will the solution cost?

Engine: I'm under the impression that these things can take a beating and last a long time on basic maintenance... should I even see this as a concern?

I am on a low budget, and don't care too too much about mileage but these cars are getting old and cheaper. I'd like one but can someone school me on buying one?

I am no mechanic, by far, so all I can say is look for the obvious leaks and such. A great clue to if the owner takes care of the care is the cosmetics of it. Are there tears, burns, etc in the fabirc/leather? Is any of the plastic cracked where you wouldn't expect it (ie: ignore the cracks on the door panels since many cars get those). Rust anywhere under the engine, the wheel wells, etc. Check the wheels from major scratches, could be a clue to if they drive like crap and hit curbs and such scratching the wheels.

Look on the underside of the hood to see if there are any signs of fluids splattering up there. A person selling a car will wipe the engine down of any obvious leaks, but may forget to clean the bottom of the hood.

Are all lights working? If he/she is too lazy to change a burnt out bulb, I seriously doubt the oil changes were done on time or any other maintenance.