He's sent us deals, introduced us to people, offered advice, and has even offered to guide us if we want to get into private lending (I would love to eventually).

*I am not a financial professional. 

Im going to make an assumption and assume that you mean you want to get into private money lending.

Using private money about 17k cost and looking to take 50k out after refi.

If you make passive investment such as private loan - there would not be any issues with UBIT, all income will be sheltered from taxes.

I have someone in mind that could make a great potential private investor.

I am also planning to likely do a flip to see how it goes as I have already built some relationships with local wholesalers and have a private lender or 2 lined up for once I land a good deal. 

I'm sure many professionals will jump in and introduce themselves shortly but you should definitely come by to the next local BP meetup!

 Mark, thank you for your offer, yes, I'm going to need your help, as soon as I can find professional advice in regards to the financing process; I think my situation is a little more complicated, I'm still evaluating the situation myself, since my visits to local banks were not helpful.

Thus, before going through the hassle, it would be benfitial to ask a professional run a various projections based on your expected income and how much you would  be donating.