plessm
I have a 24 ft, but not a bunk. found my kids wanted to sleep outdoors.
I have seen some on craigslist around here.
if you will need a WDH, I have a new Equalizer 1200. purchased it for trailer, and then bought a 5th wheel. it is still in box. I am up in Stockton.
both my units have slides, I ran them in and out to see if any binding. take a close look at the floor to see if any leaks. one thing about slider, when it goes out, make SURE the rubber seal turns correctly to keep out water.
there is great info on this site on roof care.
good luck