Air beds are fine you just put a blanket on the floor underneath. We did this few weeks ago, at the same camp we've been to for few years and always cold nights, this year we were snug as a bug in a rug. except my nose, my nose still froze so I wore a beanie to bed.
When i used to camp with my family we had to bring our own airbeds and mattresses. We also had to bring along sleeping bags and even created our own portaloo. I also will suggest to hire a van which might make things a little easier.
Vans are awesome. Especially when you have your own loo and your own bed. What i used to detest was having to get up in the middle of the night and find the nearest toilet.
When we go camping every year we hire a portable toilet to be dropped off to us. It's expensive but no clean up just pay and leave it there. We so use a tent but it go broken 2 months ago in high winds so we will get another tent. I won't afford a camping van that I would only use sparingly and a camping trailer seemed good but then that's all it does. So we bought a caged box trailer and we hurl everything in there and off we go.
When i was little my mum's side of the family had caravans and tents. We used to go down to Warranambool Big 4 beachside caravan park. One year we went to Victor Harbour camping ground. Over Easter we would go to the Kullkyne national park which was a camping ground. You had to bring literally everything along with you.
Irminsul, the idea of a van is to get one like a cargo van that you can use for multiple things, like a pickup truck. I wouldn't have a so-called "camping van" or RV for anything. I like multiple-use possessions. I'm still saving up for a cargo van here, but I may have to settle for something else, like a lightweight cargo trailer, which is also multiple-use.
putting a blanket under a air mattress is almost the same as putting a blanket on the ground and then sleeping in a hammock. Both ways you get cold air under you wicking away your body heat.
Someone from friends advised me these blankets once, and spoke quite well about them. I don't know maybe it true
Best things to use are the thermal ground pads backpackers use. The best one I know of is called a Thermarest.