@Anders227 You can create a 6th listing that would comprise all 5 tents. After creating that listing, you can go to your availability settings and scroll down to "Linked Airbnb Calendars." Choose edit and link the new 5-tent listing calendar to the individual listings. That way a booking at the 5-tent listing will block the calendar for all the individual listings.
If you wanted to, you could create new listings for 2, 3, and 4 tents as well.