I think sometimes the overall visible condition will help tell you if the previous owner valued it highly and took good care of it cosmetically. However you should have an expert check out the engines, drives and not so visible aspects of the boat to make sure you are not buying a problem to start. Engines and drives are expensive to repair or replace and a boat ain't movin without EM! Don't start your new boating ownership expierence with a problem boat.
A friend saw this boat on Ebay #300666740896 a 27 Formula, might be something like you are looking for and worth putting on your consideration list. Check it out carefully just like any boat you might buy.
Ray @ Raylar