Yes
Casita did install in the front on the floor... but discovered the front vent would leak badly when driving through a rain storm. Water intrusion is never desirable.
Scamp has install in the bottom of the closet, one vent on the side of the trailer the other through the floor.
That being said, most prefer to do a window install. The nice part is you can leave the A/C at home when it's not needed due to the time of the year or where you may be going. Less
weight is always good and that would leave all cabinetry in place for storage.