If everything is in good shape, 2 grand is not bad at all. The crank could have been balanced by atk, rebuilt by atk, or maybe hes not tellin ya the truth. Just know that if the crank does have a problem, its going to cost you some money. Usually 1000 + once its already failed, and about 500 if it hasn't, and all the other parts are in good shape. Buying and upgradeing seems to be pretty popular. You can find all the info and help you need over at the sites if you choose to do so.
Cannondale fx450 timbo stroker