Not because we had failed - this was a four-year resident entering their fifth year on the property when they got into financial trouble. 

., financial info, property condition)?

Also, the whole point of hiring a PM is to handle tenant, maintenance, and rent collection, so if your partner isn’t actively managing but just supervising the PM, IMO not worth having a two people essentially looking over the same tasks.Contributing financially for one person and the other having no financial stake raises decision making questions, such as when to sell, how profits will be distributed, etc.

As you might already know, house prices in New York are extremely high, which makes it financially difficult for me to try house hacking here at the moment.

I understand if you want to sell 1 of the lots, but I'm not sure about your concern about paying off the debt so that you own it free and clear. 

I originally wanted to do a quad but financially I know I can’t fund a project that large, unfortunately.

This eliminates the problem of increasing your debt and damaging your credit score.

Over time, I’ve accumulated more cash reserves and don’t need as much flexibility, but I’m actually in the middle of a refinance right now using an interest-only mortgage—because the pricing with the lender and the corresponding ARM is more favorable than a comparable principal-and-interest loan.The key with these alternative or "exotic" mortgage types is that you need to be financially savvy and have a solid plan.

If you are taking on debt for the STR this gets a little more complicated, but not much. 

If it doesn’t make financial sense or feels too risky, there’s no shame in passing on this one.