Am I correct in assuming I should contact the current owners of the comps and get that info from them, and if so, what are key things to compare?

The answers are quick but you must ask the right people, ask a lot of people then compare and confirm for yourself afterwards.

There is another cabin in that same resort community that is comparable in terms of condition and is slightly larger renting for about $100 per night on average.What questions should I be asking myself?   

This really bugs me when I'm trying to use sites like Zillow or Realtor.com to compare comps in a certain area.

Comparable house B rents for $2,350. 10% management fee = $235.

I believe La Pine is in the path of growth for the Bend area and prices here were 100k-200k less for comparable homes.

I’m aware of some concerns such as lack of equity compared to a normal home, etc. 

Looking back at renters with the higher standard comparatively, they clean up the unit so well, I cannot find fault to keep a bit of their security deposit.

Short term rentals you need to manage more actively compared to long term room rentals. 

They use pay information from previous applications, compare it to payment history and declared income.