While I know the optimal deal involves converting all POHs to tenant owned, is there ever a case where keeping them park owned makes sense?

The seller claims to have only collected rent each month and has no knowledge of the number of tenants occupying the units. 

I don't think I've heard of a GP charging a refinance fee, I would guess it comes out as an operating expense in the LLC so not only does everyone in a way collectively pay for it but you can write it off.

She is my go to for the exchanges and can help you structure things optimally. 

Speak in terms of “We” the collective group.

Is it acceptable to ask for a bank statement verifying rent collecting and or a tax return?

The best way to find them is to send out mailers.Some good lists to target are Absentee Owners with Equity, Seniors with Long-time Ownership and Homeowners with Low Financial Stability Scores.You can work with a list broker to optimize your list for your area.

If rent collection is an issue, collect rent twice per month.

They ask you what you want to do and follow your order and collect $.

With that being said, would you try to collect the rent until the end of May, and issue 7 Day notice to cure if it is not paid?