You have to be specific about what the deal is and its structure. 

Also, tenants will often times already have their own washer & dryer units and would rather use those instead of owner supplied W&D. 

For years, there have been claims that short-term rentals take away housing supply from renters and homebuyers and, as a result, inflate rents and home prices in nearby areas.

What are some potential structures to allocate direct expenses to the rental on primary residence property and keep the activities separate as not to pierce the veil?

Too much supply and saturation.

I want to compare these ratios.I also want a summary of features of the “high” category above.lastly, I want to know where those high properties are clustered, and if the market is saturated or not via comparison of supply vs demand growth.Hope that helps! 

You should verify this with official HUD documentation or through a HUD-approved lender.Term Until 2051:The mention of the loan term extending to 2051 or until the property is sold or refinanced suggests these could be loans with a long-term structure or special conditions.

Best thing to do would be to contact a lawyer and have them help you with structuring the note.

If I am reading the info right - Your Insurance company wants to ensure that the heating was on therefore ensuring that the pipes didn't burst due to freezing, not that there was a supply of energy to the house. 

However, mixed-use properties can create new issues depending on the construction and structure, access, and tenant mix.