These trailers are popular summer or winter homes at social clubs a the beach, and you are right, they have come a long way. Some are downright luxurious. I know of a few cases where the family has the trailer at the beach in summer, and then in the hills close to Lima in the winter. Sorry I can't tell you about the logistics of the move, but many people do it, so it's absolutely doable.
Prices are all over the place. You can get a sense of them here:
https://www.olx.com.pe/otros-vehiculos_c380/q-rodanteCheers.