Greetings. Welcome aboard C-Brats. Please give us your level of boating experience, and if you are willing to tackle issues or have the coin to have professionals (at $150 and hour) to repair issues.
I always recommend good marine survey before buying a C Dory. It should be someone who is experienced with cored laminates on boats. Moisture meter is of some value, so is ultra sound and IR photography to find the majority of possible issues with these boats. A lot can be discovered with a phenolic hammer or even a screw driver handle, tapping and sounding out the laminates.
It would take a book to explain all of the issues--and I refer you to the Yacht Survey site of David Pasceo, who has unfortunately passed on.
David Pascoe's book.. Click on the box : "cores and Structural issues" there a few articles which are must read to understand the C Dory construction...and I don't fully agree with Pascoe, but it is the most comprehensive place to start. Then read all of his other articles. You can then buy the books--but the articles do have the basis for an informed boat buyer and owner.
If you want to see issues on a 25, please see my photo album, starting on page 5 and 101 of 637 images. This shows my experience buying a 2003 C Dory 25 for $30,000 with known issues, with the cockpit deck actually with a hole in it. It had been left out in the snow in New Jersey for at least 3 winters, with no cover. Snow, rain, freeze and thaw cycles, caused extensive core damage starting around the hatches and then a hefty crew member jumped into the cockpit.
To be quick and dirty check around all of the hatches and any core penetration on the boat, this includes the fore deck around windlass, deck pipe, forward opening hatch, the cockpit deck, the hull under the fuel tank, the interior where "L" brackets hold the wooden furniture down to the hull. This are the most common places to find areas.
My last 25 was one of the most desirable 25's listed. It had already been modified and improved by several very knowledgeable owners, and I made a number of improvements. I sold that boat in 2 hours from the time of posting. But even then that boat had some issues I fixed also.
To reiterate every problem I have seen in a 22 or 25 is way beyond the scope of any post. But the above pretty well sums it.
A C Dory 25 which was listed today (Jan 20th 2023) is one of those rare boats which was owned by one owner since new, and was well cared for from what I understand. I still would check various places for wet core, but it would not stop me from buying that boat today even with some minor issues--If they are even present.
A boat kept well by a good owner, where it rarely or never freezes and the boat is kept under cover with desirable upgrades is always a most desirable boat.
