Welcome aboard!
Looks like you have your work cut out for you. First up, a good scrub down with some bleach and water to kill the mold on the outside. a weak solution will do. Then have a good look at the floor especially the ones under the front seats as that front drivers side looks like the floor has collapsed and the frame is buckling the front
fiberglass. Also check the frame in that area for bending or cracks. As for the interior, these are pretty easy trailers to redo if needed with the exception of the floor which can be a real pain as the plywood was installed when the
fiberglass shell was still wet and is bonded to the glass pretty well.
ALL posts for Ventura
Patrica, glad the door idea worked out for you, I wasn't sure but thought they may be the same size after looking at them.