When screening, what are the subtle signs of PROFESSIONAL tenants that landlords can pick up on with the trained eye as to avoid them?

There are usually better ways for sellers to go instead of selling using Sub2, it just seems to be the flavor of the month snake oil that gurus are pitching lately. 

There are subtle advantages to the BRRR concept, and @Lesley Resnick has nailed one of them - that profit gap that the flippers can't get excited about.There are other advantages too:  Say you can find a home on the 1% rule on the market. (1k rent, 100k purchase). 

Your reviews are great, it's not my flavor in colors and all that but it looks like it fits in the area etc and people obviously love it.the only thing I would say is it feels a little "commercial" to me but it is clearly reviewing well so I'm not sure I would change that.

I just read a book that had a great concept, the subtle art of not giving a F***, and it describes that the people are successful in the business are the ones that are excited about the process and the rest comes with that passion.

It all looks fairly flat but I know it can be subtle. 

More subtle though is these properties likely have rent growth that does not keep up with inflation.  

I take them a big tin with different flavors of popcorn and a box of chocolates.

So figure out what flavor of tourism is in your corner of Montana and then focus on that.

Here in CA, there are two main types: RCFE for 60+ and ARF for below 60 with various flavors depending upon the population you choose to cater and the level of care you provide.