Any advice on what sort of structure to buy / build to escape family for a few hours a day?
No issues, just sometimes it can be a bit of a pain in the ass to live with 7 people.

Lots of land.
Budget - $1000 to $2000. We have COLD winters and lots of snow.
I would dig something, but the issue is that we have no hills - and all the water will flood the place.
Thanks frens.