I'm new to vans and only recently joined this forum. One of the first things I spotted was people installing projectors and I had to have one!
Here's what went in…
Nebula Capsule 3 Projector, £399.99, I'd have liked the laser version but this was discounted at the time…
Duronic BPS50/43 Projector Screen, £29.99, this was the largest I could fit in the end of the pop top which is a standard WestDubs.
10mm Velcro, £3.90, I used this to fix the top of the projector screen.
Magnets, £13.99, I already had these for magnet-mounting a panel. They're used to anchor the bottom of the screen, and the washers for hanging the projector.
Magnetic Ball Head Camera Mount, £11.69, I only used the magnet plate in the end, but the ball head might be useful if you mount the projector differently.
Flat Black Elastic, £4.99, I only used about 100mm of this in the end.
10mm Double Sided Foam Tape, £4.99, used to attach the velcro to the top edge of the projector screen.
Pack of countersunk bolts in various sizes, £9.99, used to attach the magnets to the elastic loops. I didn't know what size I needed so brute-forced the problem with this box of lots of sizes.
The screen is mounted with temporary fixings only, nothing screwed in anywhere. Two strips of velcro attache directly to the pop top carpet lining to fix the top pole, and two elastic loops with magnets attached anchor the bottom pole.
The projector has a magnetic base screwed into it. It's practically the same diameter as the projector so almost invisible and adds about 8mm to the height. The magnetic base attaches to three washers screwed into the bed board. I put the washers on the magnet base first, letting them find their own positions, and then did a brass rubbing to transfer their positions to the bed board. They're pretty much flush, so nothing to break your head on when the projector's not in place.
So I came home and ordered myself a cheap projector and a freestanding 50" screen from Amazon, £100 all in. I didn't want to be messing with any fixings, even non permanent ones, so this seemed like best (and easiest) option for me! I've not actually set it up yet and it will probably be terrible 
but I'm going to try and set it up this weekend. Will post back with the results!
so if anyone else cba with fittings etc then this might also be the one for you!
