I emphasized the quick closing timeline and my ability to pay cash via hard money financing to strengthen my offer.

depends on your credit if you can get a mortgage or your ability to find good deals that you use hard money for and then refinance into DSRC.  

I've heard too many stories of investors purchasing homes for STR use, only to find that they lose their permit or the ability to transfer it when they sell.

The ability to do cost segregation and bonus depreciation3.

Credit is also going to hinder your ability to get a heloc, and lack of income for now. 

Through that lens I will try to answer your questions to the best of my ability:1.

If they are struggling then money they spend in one area affects their ability to pay other bills like rent.

This can put a significant strain on your finances and cash flowThey also often require a large down payment themselves and may have a strict repayment schedule that can be difficult to meet, especially if there are unforeseen circumstances or delays in renting the property or generating income from itIn addition, relying on this type of loan may expose you to higher financial stress and the possibility of default if you are unable to meet your loan obligationsThe final decision depends on your overall financial situation, risk tolerance, and your ability to manage the associated costs and obligations

So, I DON'T trust my ability to determine someone's character based on a few minute casual conversation and I DO trust my ability to manage even difficult tenants. 

You could put in a range of numbers for purchase price and closing costs, renovation expenses, and expected returns and you could very quickly get a range of projected return on investments (although an excel spreadsheet could easily do this as well), but I'm sure as technology develops we will see even more sophistication in AI's ability to assist in deal analyzing.