Probably a hole in the floor for a lavatory. I asked have you noticed drywall cracking, or floors buckling, standing three feet over the customer on a bump.
Thanks for the thought of HO doing his business whilst I consider going spelunking. Pontoons is the best option until he get a septic truck to pump it out, sice I doubt a sump pump would last long. Haha
Sorry Mike.... that inflatable was probably left by the las tech. The unit as well as the foundation was floating away. I can take a guess their static was off a bit. Maintenance, not a "no-water wings call"