My parents put up most of the money for the down payment and they're crediting 10% of the rents as equity to me each month as payment for managing the property until we reach an equal equity position. 

I have assumed their leases and added an addendum that includes a few items (no auto renewal, new payment address, etc… ) which I am planning on asking them to sign.I sent non-renewal letters about a week after closing (early April), which gives them way beyond the 30 days' notice.

You want to invest just to have a place to live and potentially offsetting your mortgage payment by renting out the vacated rooms or having x amount of cashflow in the future?

That being said on a $50k line of credit, the payment difference is about $40/mo at full draw.

Payment Structures: What are the typical payment structures for LPs in syndication deals, and how is payment conducted - quarterly, every other quarter, monthly?

But Generally, most lenders will want to see that the lease or market rent can support the mortgage payment, the borrower does not intent to live in the property, the borrower has 20% down + closing costs, 6 months reserves, and credit is above 620. 

turnkey means - you buy it with a high interest rate and high down payment, perform no value add, rent it out, and hope the HVAC doesn't go out in month 4.where or how is that 'cash flowing' right now?

I had more than enough income to pay for a mortgage on the range of properties I was looking at but I just didn't have a significant enough down payment without tapping into my 401(k) for a loan.

If not what is a good down payment price/percentage we should be looking for? 

Talking to residents power has been shut off to the park three times in the last two years while water has been shut off four times- all for non payment by the park.