We also have 4 rooms with a shared bathroom. Three of them have 3 beds (a bunk bed and a single bed), and the other one has two single beds.
The bedding and towels are included in all of our facilities. They will be changed every 4 days, when we will take the dirty sheets and towels, and we will hand in some clean ones. If you wish to have another change frequency you can hire it separately at reception.