The shower/toilet combo is a Thetford cassette toilet. They are a very common option in pop-up campers. The problem is they are a bit pricey. I got mine from a slightly used pop-up that was totaled by a tree falling on it. Fortunately the shower/toilet wasn't damaged and had never been used by the original owners. If I had to buy the shower/toilet new, it wouldn't have fit our budget. Our original plan was to install a wet bath which would have been a cheaper option compared to a new cassette toilet /shower.
Our camper door was originally 70 inches tall so it had to be shortened. Also, it is 27 inches wide and the cargo door that came on our trailer was 34 inches wide so we added a wall stud and some white sheet metal to fill the gap. None of this was very difficult but I do have access to a shop with every necessary tool to make this an easy job. Shortening the door took about 2 hours and narrowing the rough door opening took about an hour. Add another hour or so to install and seal the door and install the striker plate for the lock.
Shortening the door involves shortening the door frame, screen door and the entry door. To shorten the door frame you remove the four screws holding the threshold on and cut the door jambs with your favorite metal cutting tool. I used a metal chop saw which makes quick work or it. Than just screw the threshold back on. The screen door unscrews to come apart so you can cut the side pieces and screw it back together. The entry door is held together by rivets. Drill out the rivets, cut the door and reinstall the bottom piece with new rivets. If I remember correctly (it's been about 5 years since I did this), I also had to raise the lower hinges on the door jamb.
It's one of the best modifications we made to our trailer. The screen door is great for ventilation and the insulated door really helps retain the heat in the winter and cool air and the summer.
