Bizarrely, the only condition the guy had on us having extra campers was that there were no children. Not sure why that was the case.
We also have a double inflatable mattress (assuming we didn't chuck it out when we cleared out the garage). If the mattresses haven't improved since last time, it's probably more comfortable than a bed too.
If people want to do camp beds etc I can take more deposits - brings the cost down for everyone.