I'm guessing you are going to have to stay with the daytime seating into bed setup at night, so no fixed bed conversion.
After 11 years the seat pads should still be fine and I believe they will probably be sprung and not just foam. If they are foam you could take to a local upholsterer/foam supplier to get a gauge on how good they are and price to replace if needed.
For the new upholstery fire retardant is obviously a must. I'd also bag the old covers and keep in the loft for when you eventually sell, just incase.
Sleeping wise I believe most people with your set-up use sleeping bags or duvalays and roll them up for during the dau. Because we have always used a fixed bed set-up we have gone for duvet and sheets. If you are on a long summer set-up abroad and basically living outside then you could easily revert to this method

Colin

We decided to add some 2" memory foam (1" when compressed) to the top of our existing seats and then to recover the whole lot leaving the original covers inside. Like you, we didn't fancy the storage problem of mattress toppers.

The above arrangement worked very well but we have to admit that after 8 years they could do with renewing as the foam has shifted inside the covers.

The first thing to consider though before you start adding thickness to the seats is the headroom when sitting to the underside of the roof locker boxes. Not being very tall, it worked OK for us.

Randa

Quote: eribanaut wrote in post #4

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I just wouldn't like to sleep on a mattress someone else had slept on for 11 years, a matter of hygiene. you wouldn't buy an 11 year old mattress for your bed would you?.
Dave

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