Yes i am in the Bronx market and looking into closing on a 2-4 family unit property. i am currently looking into different methods of creatively funding the deal and looking into partnerships to create capital. .

What you want to ask is if they are a direct lender funding and servicing your loan

I have a few Airbnb properties for sale with creative financing in San Antonio, I'll shoot them your way just in case. 

You do have to get creative.

The homeowner has direct title, can sell at any time and gets 100% of the appreciation and tax benefits on these houses.

Has anyone done anything creative in the past with a detached garage besides turning to ADU?

Your taxes are none of the ex wife's business and this would seem to address your concerns.I would also put her on notice that future requests for financial discovery will be two-way and if a discrepancy is seen in the other direction you will seek support from her.

I doesn't sound like you have a lot of experience doing creative finance deals, and your overblowing numbers crazily.2.

I’m going to disagree with @Chris Seveney and say whether an assignee could force a sale directly would be a state law issue and heavily dependent upon the contract terms. 

But for many people, it is one of a number of sources of deal flow, to add to MLS listings, wholesalers, direct owner outreach, auction, etc.Assuming you are specifically talking about sheriff auctions, just make sure you familiarize yourself with the general procedures for the auction.