So I currently have 65 long term units that I own and I recently purchased my first property that I'll be going the STR route with.

Basically, I just bought a large (4300 square feet) cabin on Lake Superior that is essentially "split" into two different houses that are connected via a door through one of the bedrooms.  One unit will sleep 8 people comfortably, and the other unit will sleep an additional 10 comfortably.  I'm beginning to decide on my strategy for renters and marketing.  For ease sake as well as cost I was considering making my base rate on 6 people staying, then charging additional for each person with the expectation that if they have more than 8 people they will then gain access to the 2nd half of the cabin.  I was simply going to have an electronic lock on the dividing door (there are 2 separate entrances), and give them access based on # of people.

I don't plan on renting them out individually, it'll simply be either access to only the main part of the 1/2 cabin or the entire thing with the number of people.  It's in a more remote part of WI directly on the lake and I'm attempting to save on cleaning costs/time/maintenance costs by going this route as well as make it more marketable to smaller groups.  Anyone ever done anything like this?  I was considering using my maximum number of photos on AirBnB and VRBO and then make it very clear in the description that you'll have access to the first x amount of pictures etc of the cabin if you have 8 or less people and attempting that route while still maintaining the flexibility to go up to 18 people in the house.  

Any advice I'm all ears!  The main cabin has all of the desirable traits if you will, views of the lake.  Other than room for more sleeping there is nothing on the side of the house that would be a main selling point for a renter.