Re: putting a door in
You mean a walk-through transom?
Any big boat shop (as in one that works on ocean going boats) can do the work, but it's gonna be expensive.
Any boat that's not designed to have a walk through transom from the start will need to have its transom replaced and reinforced to permit one.. basically you're removing a big hunk of an important part of the boat, a place where it needs lots of strength and stiffness.
Usually the reinforcement is either a thicker transom or extra structure around the new door. Plus you need to relocate anything that's in the way of the door.
It's really not just a matter of cutting a door shaped opening and making it look good. If you run across a boat shop that suggests that's all that is needed, I'd recommend looking elsewhere.
That said, any shop that works on boats that size regularly, preferably employing or working with a marine architect on site should be able to do the work.
Erik
