Every day, check the boats for sale by owner on this forum, C Dory facebook page, Facebook boats for sale, and Craig's list nation wide. Also check Boat Trader, Yachting World boats for sale. They turn up in unusual places. If a what appears to be a good boat, then jump on it right a way--they can sell fast. Be ready to put a deposit of 10% to hold the boat before a survey/sea trial or at least you inspect the boat, with a sales contract.
Many boats never reach the C Dory market place--and someone bought them before they hit the open market. For instance a bank having to liquidate an estate with a boat they know nothing about.
As far as age: The 25 comes in several versions. The first set was 5 or 6 boats built in 1995/96. My son owns one of these, and it is a very good boat. The interior is different--the galley area is narrower, and both the head (port side) and Dinette (Port side) are both larger than the later boats. There are no windows and only a small window in the door. My son uses a "back up Camera" for most rearward vision.
My First C Dory 25 was a 2003. It had been badly damaged, and I had to do a bit of rebuild--but it taught me more about the structure, and after we were through, it was stronger than when built. The second and current reiteration of the C Dory 25 started in 2002 (I believe). The general layout and hull etc are the same as the new boats today.
There have been gradual improvements. Early boats had a large holding tank under the splashwell. Around 2005 the boats had a the head changed to a internal 9 gallon holding tank, and the fresh water was removed from under the V berth to under the splash well. In 2006-2007 the interior went from being Decaguard plywood covered with a melamine type of laminate with "L" brackets holding it in place to a fully molded fiberglass interior. The more recent boats can have a vinyl foam backing headliner and and cabin side liners. Sometimes these delaminate. Some fuel tanks last for 20 or more years--my son's boat is close to 30 years with the original tank. Many of the newer boats are fitted with up to 200 hp (small block--4 cyl) outboards.
