As a new realtor (and student) you probably make below 80% median income which might help you qualify.I work with Finger Lakes Federal Credit Union (for my primary) and Lyons National Bank (for my investments), both will probably be able to help you navigating downpayment assistance and your situation. 

Bank Credit Line How did you add value to the deal?

Specifically, I am looking at partnering with an individual who owns securities (stock and mutual funds) having them take out a line of credit against their portfolio (SBLOC) at a low interest rate, and using that to purchase properties rather than using a mortgage.

I can do that for you if you are properly prepared with reserves and credit.

But somebody could use a credit card fund the immediate need and then pay it back with the policy loan fairly quickly.

I've read so many horror stories on this forum about terrible PMs. 

@Randall AlanRandy,I have roughly 1+m of funds, that includes open lines of credit.

Often you can find these lenders with a mortgage broker or by reaching out to a local bank or credit union in the market you wish to buy.Cheers!

Your name and credit would stay with the existing note, which you would keep paying on - ideally yourself with money you receive from the "buyer", because if they don't pay your credit is wrecked and your house is in foreclosure.If you search on here you'll see everyone and their brother looking to do Subto and it's a nightmare unless the buyer has the funds to pay the note off if/when the original lender figures out you don't occupy the property any more and are attempting to do what you want to do, since most loans are going to specify that performance.  

You definitely want to use a thorough screening method like rentprep.com that gets their income, credit, background check, and call at least 3 references (make sure to verify them by address/job and then their name).