It really depends on the model. I've seen some models with bunk beds that were easily removed without damage, and easily replaced (so the next owner would have the same functionality). Just took a screwdriver and two people to lift the bunks out. Other models, the beds, once out, are out permanently, so replacing them would require a remodel.
If length were not a factor for me, there are some 30-31 foot "C" floorplans that have two bunks by the master bedroom, and if those were removable, it would be an ideal spot for a desk/half-dinette and chair.