Re: moving boat off the trailer...
Not hard to do at all. I helped the guy that hauled and block my boat for the winter.
Have enough blocks to block the boat. I have a 27 Regal, and I think we used 18 blocks, and plus wood.
I started my blocking with 3x3 pieces of plywood, because it is on my lawn, if you are doinf it on blacktop, I would not bother.
Remove the stern straps, and loosen the bow strap about 80-10 inches, back the boat up and hit the brakes, you do not want to go fast, just enough to move the boat. The boat will slide back and take the slack out of the bow strap. Keep doing this little by little, until the boat can be pivoted on the trailer. Have someone stand on the trailer tounge, and hold down the bow of the boat. Block the back two corners of the of the boat. place two blocks side by side, under the corner, then place to more blocks on top of these, but change the direction of the blocks. Keep building the pile until you can not fir more blocks, then finish with wood.
The back of the boat is now supported. Now slowly pull the trailer forward. you want to get about 2/3 of the bottom of the boat exposed.
Build another block pile under the keel, again have someone stand on the trailer tounge to raise the boat. When you get that pile tight under the keel, the trailer should slide right out from under the boat.
Before you do any of this, you must make sure that, your bow eye, and bow strap are in good condition. I have also seen it done, by backing the trialer/boat up to a truck, and taking the stern straps and attaching them to that truck, the slowly pulling forward with the tow vehicle.
Either way go slow and take it easy.