He doesn't have an electric fresh water pump as he doesn't want things that break. HUH?, carry a spare.

I personally like polycarbonate. When it hazes in the tropics (6 months), I polish it out with a buffer and get new windows, cool. It's also stronger than any other transparent material available by weight because it's soft and flexes instead of breaking . Ours have been good for 12 years with only one leak that was the fault of sun on the GE-4000 bedding material. We really like the GE-4000, it's a hi-rise window sealant and isn't available from WM. There may be something better as it has been 12 years but it's serviced us well.