Last weekend I looked at adjustable beds. Found a really nice, and comfortable, one at sit n sleep. But then I asked about the foam mattress and found that if there was an accident I would have to clean up right away otherwise the mattress would have mold/mildew. For all that money, I can't bring myself to purchase something that may not last more than a few months. I did check on hospital beds but they are rentals and used. With all of the fuss about bed bugs and not knowing what the last person who used the bed had, I worry about getting a used hospital bed (that's what our insurance HMO has to offer and I checked elseware and they also rent used beds). So I am guessing I'd better stick with what I have for now at least (a king size bed we both use).
The mattresses that come with a used bed are covered with vinyl and the company provides a plastic mattress cover. I then put an egg crate under it and a cloth mattress cover over it. It was clean and comfy. No chance of bed bugs :o)
We did get a hospital bed, paid for by insurance, but then I bought a new mattress for it--one of the air adjustable ones. Some but not all models of those can be used on adjustable beds. My husband is early stages and I have a waterproof mattress pad on the the bed; I don't know if a vinyl covered mattress would be better later on. I did keep the mattress that came with the hospital bed (in the attic). It looked new. The deal from our insurance and supplier is that the insurance pays to rent the hospital bed for 10 months or a year and then you own it. I assumed that since we expected to keep long-term they would give us a new one.