Cassie,

Back on the trailer option. It might be worth approaching a trailer builder and getting a bespoke design done for you. You can buy the exped type tents that fit on top of the trailer from MyWay Roof Tents (UK).
The advantage of this is that you can have all the things you need and not waist money on things you don't need. I had a quote for an adaptation to a Sankey wide track trailer for under a grand. That included secure lockers and split charge system.
If you google bespoke trailer builder a few come up.

With the internet it should easy to keep the kids up to date on key skills, I agree with edbell - your kids will get an oustanding education in life.