I believe interest is tax-deductible if used for property improvements or purchases, and it gives you quick access to funds while keeping your stock portfolio intact.Private Money Loan: If you have a trusted partner and terms that work well for both parties, this could be an efficient solution without tapping into your other assets.

Lots of people rent houses for parties as well, and you won’t be able to do anything about it.  

Blood gets thick and the worst part is 10 years later there are new voices in their ears, telling them all kind of crap and filling it with all kinds of ideas. 

However, you can make changes as long as all parties agree.If the tenant agrees to removing certain clauses, or starting with a new lease, then you can move forward.

It's difficult to say if the partnership structure makes sense for all parties without knowing your exact involvement. 

My #1 fear going into this was partying guests disturbing neighbors and damaging the property.

Happy you joined the party.. how soon do you plan to start crunching numbers on a potential deal?

Additionally, by virtue of owning all of the units I could, with the help of an attorney, construct the bylaws in such a way to maximize value and eliminate bylaws that would be value-restrictive.I've talked to a couple of non-QM lenders who could provide financing to buyers under such a scenario, but the tricky part is appraisal value, especially in a state where, according to Redfin, no co-op's have sold in the last 5 years.If I got a couple units sold using seller-financing at $220/sqft, since there aren't any other co-op comps, would this provide a basis upon which an appraiser would provide a valuation closer to $220/sqft than $135/sqft?

But the best part is the guy I rented to is going to take the super job (trash, sweeping, snow, minor fixes) so that really like 3000-3100. 

So, just so I’m understanding correctly, unless the ADU has a driveway for parking of its own, then rent rates might go down on the actual house bc, essentially, the property land is being shared by different parties?