I've used automotive upholstery cleaner as directed on the can. Then I take a damp towel and wipe it all down. Then I use my shop vac with the filter removed and suck it up as much as I can. Then I leave the trailer as open as I can to dry with a circulating fan inside.
Tuff Stuff/Tuff stuff foam cleaner 00350 at AutoZone.com - 1 reviews
This stuff has a strong smell of its own until dried and dissipated for about a week. So plan ahead especially if your sensitive to smells.
Its far cheaper and easier than replacing rat fur.