I have two units left And my rehab will be complete however I am left with very little capital to continue investments with (down payment + rehab costs for 5 units).

We have used various methods to save up for down-payment funds: we set aside pay raises instead of consuming them, re-enlistment bonus sums, tax-free income from deployments, an inheritance check, the tax-free savings account while deployed...And so forth.  

My payments are 689 a month.

Ask them to give you your main constraints... 1) minimum down payment % by property type (will vary for condo, SF, 2F, etc) and 2) the max loan amount you can carry.

The property was seller financed and the last payment was paid for over a decade ago and we've been using the property for business since. 

I want to do flips but I'm hearing wholesaling is good start for quick cash but I planned on using dad for down payment being I don't have cash for it?

But if your first loan is a 15 year, then you'll have to put a down payment (20-30% down) AND have to fund all the repairs.

Also how do I make sure he is making his monthly payments on the property?

The only reason I did not move forward was because I want to use leverage for my purchases while they prefer cash, and while their COO Peter was very cool and said they could potentially do my deals, the loan had a balloon payment at the end which is not the type of loan I am looking for.

Just because they can give me a large down payment doesn't mean they will pay me on time every month.Thanks,Kelvin