I don`t know why it wouldn`t work. There used to be a guy in Central Florida area that had an old teardrop trailer all done up as a diner inside, and towed it around to shows.
If you want a pump that lays down when travelling, I would think you`d want to weld a heavy duty hinge into the framework of the floor though, something that would withstand the weight of a pump. (Just the frame & skins of a pump are still pretty heavy.)If it were me, I`d buy a bare frame of a utility trailer and build it specifically for the purpose....may be easier than trying to adapt a trailer that`s already built.