To set the numbers of slides that are allowed on a specific site, follow the steps below!
In the main settings cogwheel, navigate to Units -> Units.
Find your RV Site units that need to have their allowed slide count modified. You can either use the searchbox to find a specific unit, or you can expand the units tree by clicking on the Site Type, and then clicking on the Unit Categories within that type.
Once a unit has been selected, to change the number of allowed slides, click on the Slides drop-down menu, and select the number you allow on this specific site. If there is no restriction, you'll want to set this to "N/A".
Once this is set, be sure to save!