Why can’t the family stay at the hotel on the following weekend?

M: Thanks for calling Quality Inn. Anderson speaking.
W: Hello. I’m interested in booking a room for the following weekend.
M:(4)I’m afraid we’re totally booked for that weekend. There’s a convention in town and we’re the closest hotel to the convention center.
W: Oh, I didn’t realize. Well, what about the weekend after that?
M: Let me check.(5)Is it Friday on September 17th?
W: Yes.(5)Friday and Saturday.
M: It looks like we have a few vacancies left. We recommend that you make a reservation, though. It’s still considered peak season then.
W: OK.(6)Do you have any rooms with two double beds? We’re a family of four.
M: Yes, all of our rooms have two double beds.(6)The rate for that weekend is $129 dollars a night.
W: That’s reasonable. And do you have cots?(7)One of my daughters might be bringing a friend.
M: We do,(6)but we also charge an extra ten dollars per person for any family with over four people.(7)The cot is free.
W: OK,(7)hut I’m not positive if she is coming. Can we pay when we arrive?
M: Yes, but we do require a fifty dollar credit card deposit to hold the room. You can cancel up to five days in advance and we will return your deposit.
W: Great, I’ll call you right back.