Your other questions are better suited for an attorney to avoid misinformation.

However , properties taxes are due like roughly 12k for the two lots. 

Credit Rating/Bank Statements/Tax Returns: Specify your requirements, if important to you.Purchase Criterion: How do you define a good deal, which will be profitable for your borrower and safe for you?

I would recommend an STR for the best tax benefits and cash flow no doubt.

BRRRR, Fix Flip, taxes, deal analysis, market analysis, marketing, financing, etc.  

Background checks on how well they avoid trouble.

I was just reading Mark's book "The Tax & Legal Playbook" this morning and it specifically had a "critical warning" (page 31&32 in Chapter 3).

You and your legal, tax and financial advisors should review this transaction in greater detail, especially the PLRs, to ensure you understand the significant risks involved and are structuring the transaction as close as possible to the PLRs to mitigate some of the risks.

How should I phrase my interest in the property to avoid coming across as pushy or insensitive?

Quote from @Erick Pena: A "good" rental property is one that covers all expenses (mortgage, taxes, insurance, maintenance, property management fees, and any other costs) and still leave a surplus (commonly referred to as cash flow).Calculate cash flow as: Cash Flow = Rental Income − Operating Expenses − DebtThere's much more to it, but that's the basic idea.