Because I used a NNN lease where tenants paid for their pro rata share of association dues, taxes, and insurance…..

In this structure, the tenant pays a base rent amount and their pro-rata share of the property’s real estate taxes, insurance, and common area maintenance, commonly referred to as “Additional Rent.”

A seller would typically be responsible for their pro rata share of such a bill (buyer would need to confirm the applicable contract language).

For GAAP, you'd amortize the loan origination fees over the duration of the loan and recognize the expense pro rata each month of the loan term.

You might run into adequate HVAC capacity and needing to run additional ductwork (then determining a pro-rata billing set up perhaps) or even an additional unit with separate water meter just the same. 

My concern with that is the whole giving the rat a piece of cheese. will there be something else that bothers him?  

@Graham Kuzek also note if you lived in property as primary or converted to primary after using as a rental, you may be eligible to claim some capital gains exclusion on a pro-rata basis.

That would actually work well with a DST because part of the purchase of a DST is a pro rata share of the non-recourse debt. 

Problems arise because some owners don’t want to convert; because some owners can’t qualify for condo loans ( even if they own their co-op apartment free and clear they’d still be responsible for their pro rata share of the underlying cooperative mortgage), and because owners realize that when co-ops are converted to condos the taxing authorities will value the property differently; coops are valued as rental buildings while condos are valued as individual owned units, usually resulting in a 50-100% increase in property taxes.

There are three GP's, the capital partner, the operator, and the fundraiser... 30% equity stake in the GP is reserved for raising a total of $1M, it is pro-rata.