Like any car, watch out for rust, electrical issues (unless you are good at fixing them and or like electrical issues) and funny mechanical noises.
One thing I like to check for when looking at a TR is to see if it has been returned to stock, ie. did it have an alcohol kit, K&N air filter, etc. in place and is now being returned to stock to be sold. If the seller says it is all stock, never modified and everything under the hood is dirty except for some stock parts that were just replaced then I know he is lying to me and to look for other issues he might be trying to cover up.
I don't mind the car having performance parts and on it, hell most of us add them on but I really don't like liars trying to dupe me because then you can't trust anything from them.
Just remember it is probably cheaper and easier to fix mechanical issues than it is to fix rust issues.
Good luck,