Mind sharing which bank/financial institution you used? 

Heloc's sound cool because of the flexibility, but it seems institutions don't want to give LOC's on investment props. 

Just as I would not expect an institutional investor to buy and manage homes, I don't think I'll be doing that with the SEP either.Here's my recommendation:Hands-of investmentf: Go with the SDIRAHands-on (or potentially hands-on): Go with a typical (non-IRA) process

How are fellow investors paying multiples mortgages on multiple properties; especially if they are financed through different institutions?

It has solid cash flow and great tenant currently living there.Can anybody recommend me a bank/credit union/financial institution that can provide me 200K HELOC  (up to 70% LTV)?

The US subsidiaries of Canadian banks are leery of financing Canadian purchases in the US unless the borrower has a significant and deep relationship with these institutions in Canada. 

And the 100+ parks that were sold to PE are institutional grade parks.6000 spaces free and clear is a cash flow monster.

That's true, and that's why institutional lenders can lend you money at 4.5% or 5.5%.

My plan A to keep the note (notes) for 2-3 years and than sell to probably an institutional investor. 

You cannot purchase the property personally and then assign or transfer to your IRA.Any self-directed IRA vehicle will likely take 2-3 weeks to establish, largely due to the timeframe involved in moving funds from your current institution to the new institution.