I told him that I still want to make one on the small utility trailer. I'll make it a single person standie. Even if we never tow it anywhere, it will be good for a spare bedroom if someone wants to visit and/or we can just use it to store all the SCA stuff. He's OK with that.
In the meantime, to get used to working with this material, we decided to take a practice run by making a chicken coop and it's going to be a castle. It will have stones carved into it and have a papier-mâché shell. Crenelations will be added on top. It will have handles coming out the ends so that we can pick it up and move it around the yard. Will be nice to have a coop we will never again have to clean out! The handles will go the entire length of the thing so that they're also the roosts. We won't be putting nest boxes in it cos for some reason they like the cardboard boxes by our front door.

The bottom will be chicken wire with a skirting so that nothing can dig under it.
It took me 2 days but I managed to get a layer of papier-mâché on the corners before it started raining the other day and today I managed to get 2 windows and 2 arrow slits cut out before it started raining. Weather is supposed to clear up by tomorrow and be nice for a few days after that.
Eventually my little standie foamie will be similar. I was going to go Tudor with it but after doing the carved stones, I decided to go Gothic.
This is a test piece I did with the stones. Husband liked it so much he was asking for the entire coop to be done this way too. I said that I'd love to!
Update: We got all the cutting done and the roost/handles installed. Looking forward to better weather starting tomorrow.