surcharge - minimum?

I am adding tours as options to the booking. I can specify number of guests, but I need to set a minimum to make it worthwhile. Such as a minimum of 4 people

The Multiplier allows starting to charge people after a certain number, but that is no help.

Optional Add-Ons
"Add 1/2 Day Local Tour - JW for 3 guests for $285.00 + tax (What is this?)"

You could use the Booking Criteira on the surcharge (low down) to define that it must be for Guests >= 4. But that would make it disappear as an option if the quote/booking had 3 or fewer guests. Is that what you want?

The addons are for tours locally. It's not worth spending a half or full-day for one or two people. The idea is a booked group wants to take this, but I just want some way to require at least four people to make it worth my time. I don't want one person to book and then I have to explain to him I can't do the tour.

Then the booking criteria should work for that. Set booking criteria to number of guests >= 4 on the surcharge.

OK. I understand. People at several different properties might be interested in the same tour at the same time for or greater. But that seems unlikely. So I prefer to stick to one booked group, 4+ people, I can offer a tour.

I have a complex, rich website for tours, but it is intended to start next year. MountainManJourneys.com. It will be using an Icelandic PMS owned by TripAdvisor. .

I wish there were a way to do real packages: vacation rental + tours + other services.

For this year, I am just intending to offer local tours to people as a vac rental add-on.