DeFever designed many one off vessels. He was not necessarily the builder. In looking at the pictures I see a few DeFever give aways, but knowing the build site would be helpful.
It does look like a very nice vessel, but as always the devil is in the details with a thorough look over by an experienced person. For sure the integrity of the fuel tanks is a must especially if the teak decks are screwed down. Also, knowing the details of the engine rebuilds should be ascertained.