If it is only short term, why not go with the HELOC, as long as you only pay for what you draw (only option where you don't have to pay interest on the entire balance up front, and is interest only, allowing you minimal payments until you finalize and sell the flip, providing for the biggest cash flow of all the options. 

I want to be able to calculate minimum payments as I pay down the balance over time. 

@Emmanuel Ayobamibo Afuwape it doesn't make much financial sense to have $6k-$12k sitting in a bank paying maybe 2% when the balance on your credit card is costing you 15%-20%+  Keep enough for your emergency fund and put the rest towards the CC debt that is a guaranteed return.

It's all a delicate balance of risk vs reward and rates of return vs time. 

You might want to pursue an investor who could invest 10-15% of the down payment and show a balance sheet for cash reserves.

Or is that just the natural balance resetting itself?

If they improve the reporting feature, I'll probably start to recommend to some of our clients, but not until they add the balance sheet to the report list.If you are scaling up, I would recommend accounting software over spreadsheets.

All that being said I think having a few balances a portfolio out some, but I wouldn't pay more then 25k for a 3 bedroom that is rent ready or very close to it in Portland.

I have life insurance with him as the beneficiary to cover the balance in the event of my death. 

Seems like bad form if you spent time pitching a seller on the benefits of seller financing only to refinance the deal and the bank pays off the balance of the note all at once.