Inflatable mattress

Have you considered a mattress topper? I reckon it’ll be far, far less trouble than inflating a blow up mattress with a (noisy) compressor every night and reversing the process in the morning. Sorry but that's the stuff of nightmares.

As TW says, have a look at this video with might help

https://www.youtube.com/watch?v=wH-F9YbvNFc

In our tenting days we used to have Coleman airbeds. You will find many for sale online. They are good quality and were surprisingly  comfortable. However, in a tent we only had to inflate them just the once for the duration of our stay. Doing it everyday could prove to be a pain as it takes quite a while.  You would also need to buy a small 12v / 230v pump which both inflates and deflates them. They are indeed quite noisy. 

Thank you for your suggestions, I had originally looked into mattress toppers, duvalay more specifically and I wasn't sure it would alleviate the problem but I think we might revisit these again and perhaps try it before going into the inflatable mattress idea, as mentioned the noise and faff of inflating and deflating each night and morning sounds like more hard work than necessary!

Thanks again, Sarah 

I’m sure an inflatable will drive you mad. I don’t feel it’s the answer. 

If your existing cushions have collapsed or lack support, you could check out getting new ones made from a different quality foam. Any good upholsterer should be able to do the job reusing your own covers.