Thinking outside the box for how you would like the "hang out space" to be — and who would be in there — say for example the mountain home is multi0generational so gaming spaces plus a poker table for grandparents and kids to play UNO or what have you also works.

I grew up learning maintenance on properties my parents and grandparents had in Akron, then started buying my own after college.  35 years later, been full time for the last five years or so.  

Keep in mind that this third party cannot be another prohibited party (e.g. grandparents, parents, spouse, children, children's spouses, grandchildren, grandchildren's spouses, business partners, etc.).It's also worth noting that while hiring a third-party can resolve the prohibited transaction issue, it will not solve the UBIT issue. 

We did get a lot of mileage out of it with the kiddos and grandparents those first few years.

What about my grandparents that don't live with me?  

Ask the grandparents if they want ANYTHING that’s in the unit.

Hey BP forum So I own 2 rental properties one I bought 15 years ago just believing in what real estate can do for my family and one I was inherited from my Grandparents.

Also I can tell the kids take the rooms upstairs and parents and grandparents take downstairs rooms.

Could be an uncle, aunt, parent, grandparent, friend, associate etc.

I lived there for years, and my grandparents had a house there for almost 70 years until we sold it this year.