The trailer will probably be fine, but it's painted, not galvanized. Also is a roller trailer, and most (in my opinion) prefer bunks.
Now for some shameless advertising. I have an EZ Loader, bunk, single axle trailer, in very good shape, but the brakes need flushed. I bought a tandem axle last year, but haven't tried hard to sell the old trailer. If you're interested, give me a shout.
I had a painted trailer. It was bad, because I used it in salt water. DO NOT USE A PAINTED TRAILER IN SALT WATER. EVER. As mentioned above this trailer is painted. Ad mentions it was never used in salt water. This was for a reason.
As for me, my only excuse was it was my first boat trailer.
One more comment. Rollers are the only way to go, in my opinion.
I've had both rollers and bunk. I'd have to disagree with Boris. I find the bunk much easier to load. But of course it all depends on what kind of ramps you are using. Colby
Beside the painted trailer (and with a painted trailer, you need to look inside the tubing, as well as the outside (Hot dip Galvanized should coat the inside of tubing) for rust. I would not consider one for salt water.
That trailer is set up for a deeper V--and although it could be modified, the C Dory is going to higher than I would want for easy launch on shallow ramps.