I guess it is not that popular lol. 

The 30-year fixed portfolio loan with an intro 10-year IO period has been popular for clients of ours!

Its  actually Stu Richards with an s but I think the other three are your best bets.

I know its popular, but I work in a gray building (inside and out) and not one soul there likes it. 

That’s the best bet.

My girlfriend and I are interested in buying into the upper Michigan STR markets (Traverse City, Charlevoix, Petoskey, Bay Harbor, etc), hoping we can take advantage of the hot vacation rental market up there in the summers and the popular ski slopes for the winters. 

Yup you would, It is nike.Now look at this graph.The reviews tap is in between the how it works and the our company tab.It is not the most popular tab.

I'm just curious how popular the town is.

Best bet may be a cash-out refinance DSCR Loan - what is the current financing/equity situation on the property?

What's the best option with low DP then the traditional 20%.. lastly of you have a awesome lender who is creative and can make it happen, please share contact Info. thanks  Sharing this article I published last year here on BiggerPockets on this exact topic - things are generally the same as when this was written up last Fall - your best bet is likely STR-friendly STR Lenders - ones that will use forward-thinking methodologies like AirDNA, etc. - probably about one third of DSCR lenders are STR friendly at this point (most will not do STR or have very conservative UW)Short-Term Rental Loans: What Are the Options and How Do DSCR Loans Stack Up?