Craigslist or Facebook marketplace did came to our mind at first but we are afraid to find someone who would randomly stop paying rent and become a pain to evict. 

It's anecdotal cause I don't care enough, but we have one STR on our property and are surrounded by STRs on all sides and there are folks in all every week including the heat of the summer. 

If you do go the LLC route I would pay more attention to the LLC Operating Agreement than the concept of an LLC.  

He thinks that means he doesn't have to pay the lender and has not been paying. 

You are in the right place to meet a lot of great folks. 

I was thinking it may be closer to a "wash" or, maybe only slightly more only bc w/ a duplex at least we aren't paying for two exterior wall materials for two sfh?

Do you pay closing costs to them? 

Pay for the subsequent tax bills for the following 4 years.

You mean folks who sue for cold calling them b/c they're on the DNC list?

Just winning the bid and paying at the auction isn't the end of it.