No, you do not need to take in a few extras for one night. Have they already checked in or are they trying to renegotiate a current reservation to come?
You do allow for up to 4 people with an extra fee for the additional guests. You could insist that they pay for 3 guests for the entire stay.
We recently had a similar situation and the husband was only staying the weekend but the mom was staying a full week so we allowed the cheaper rate for those 3 days. After the fact, I realized, my home is not a flop house where people can pick and choose when to pay. If they were staying in a hotel, it would be one rate regardless of the amount of guests but as an Airbnb host we charge by the person as a courtesy in the sharing community. Your extra person fee is VERY reasonable, it would be a $120 for 4 nights for those extra folks - hardly a hardship in NY when you compare it to the cost of a hotel room for 1 night.
Since I've been through this, if you do decide to take them for the one night and need to charge the extra fees for the extra guests for one night, you can do so through the Resolution Center and make sure they accept the changes before they check in.
Good luck and hopefully it all works out.
