What's he been sleeping in? A regular bed? So it's just the height you are a bit worried about?

We are going to get something similar for DS when he is a bit bigger...

I'd let him play in it for a while to get used to the height and getting in and out. Can you set up his other bed somewhere in the new house, temporarily?

I think the height and the getting in/out will be the biggest adjustment and if he has a chance to get used to it before actually sleeping that might help.