Dry-Storage vs Wet
I too have a trailerable O'Day 25 (1976 model). My trailer is a very good trailer, and I had originally planned on keeping it in my driveway. Once I got home, and found the trouble it is to reset the mast, I decided on dry-storage.Our marina's dry-storage is much like yours, close to the ramp, and no need to unstep the mast. However, I quickly discovered that backing that huge trailer (my trailer is a little over 30' long) into the area assigned was almost as much trouble as stepping the mast. Plus, getting the boat on and off the trailer is a bigger task than it sounds as well. The cost at my marina for a wet slip instead of dry storage was a aabout 2.5 times (a little under $2000 for the year for wet slip vs a little under $800 for dry storage), but we bit the bullet and went for it.2 years later, I think it's one of the better choices I've made about the boat. I don't know where you are, but here in North TX we can sail year 'round. Of course, during the winter, it's less "assured" on a given weekend. But, we definitely get more use out of our boat because it's slipped.A number of times we've been visiting with family, or talking with friends while out to eat, and have heard "We'd like to go sailing with you sometime". It's so nice to be able to say "how about now?" and be on the boat motoring out of the marina 30 minutes later.So, we now use our trailer to move the boat to the coast, when the urge hits us.As far as the rest of the advice here, it's right on the money. We have bunkboards as well as keel support. The keel support holds most of the weight, but I would frankly feel uncomfortable with rollers instead of bunkboards (I like the added "friction" driving down the road). In your situation though, rollers would probably suit you better.