I used to run an airbnb for max 5 people:
- 1 king
- 1 queen
- 1 single

I would provide sheets, towels, pillows etc. based on the number of people that were going to stay there. This is why the pricing is different.

If you indicate only 1 person will stay there and you turn up with 4 people you may end up with a problem.

That is aside from the fact that the owner may block you from coming in at all.