The phrase "sole occupancy" means that someone is the only person using or living in a particular place or item. It suggests exclusive or individual use without sharing with others. Full definition
It has just 20 en suite rooms and guests enjoy sole occupancy of a double room. (thetravelmagazine.net)
You will have a choice of double or twin rooms for sole occupancy. (friendshiptravel.com)
The standard garden rooms have one double bed and are sold on sole occupancy only, the luxury garden view have the option of a single king or two queen beds on request. (scubatravel.com)