Price calculator in booking system (Acuity)

Hi there, I hope someone can help me.
I am building a website for a catering business.

The client wants a booking system with the following features:

• Book day of the event and sync it with her personal calendar
• Final price calculator based on previous questions (number of guests, type of menu..)
• Ability to receive payments

Acuity doesn't allow me to calculate the price based on the number of people.  Then I've looked into other solutions like Calconic but they don't have the booking feature. Does anyone know about software with these functions and that can be integrated in Squarespace? 
Otherwise, would it maybe be better (and possible?) to add custom code to Acuity in order to achieve the price calculator?

Thank you so much in advance!

I am looking for something similar. Has anyone come across a 3rd party plugin that might work?