None of the institutional investors were present. 

Are there any credit unions that will allow for this or other lending institutions that do not need to follow the Fannie/Freddie lending guidelines?

The tech has been proven, institutions on the move.

Net worth to cosign with is another.Lacking that, (as you said, run them) offering property management might work for some.But for some that will not work if the lender requires an experienced property manager in order to make the loan.Skills:Some of the things you should understand:  1. underwriting for large complexes to know what's a good deal and if you want to participate in the deal risk wise,  2. how partnership splits are handled accounting wise so you know what you and they are getting; and  3. how the IRS looks at transactions and income from group investments so you know what you're getting into and can make intelligent decisions from a tax standpoint.

Do "subject to" deals usually need a financial incentive, such as a "relocation allowance" to entice a seller to participate in the deal?

This is based on my 3 year experience with one tenant in a condo (yard maintenance and utilities included), but hopefully the input is helpful.My only issue with it - should you wish to not renew the lease, it can be difficult for the tenant to find new housing that participates in the program. 

Every institution has their own "overlay" on top of FANNIE that can move DTI up or down, some go as high as 50% depending...Non DTI lenders:  once you have a few FANNIE loans even way shy of the max 10 you run into these DTI and not mentioned yet "reserves" limitations. 

On April 1, 2019, I am participating in a BP 90-day challenge to purchase my first multifamily property.

I need to get more accurate numbers in order to get better analysis from the forum participants. 

I’ve known a couple of different people who have participated in this exact situation and it worked out flawlessly...