Need to add custom functionality in WIX

Description

I need a WIX developer with coding experience who can add a custom functionality to a Wix Hotels app. I need a feature in which:
I need to be able to add a booking system for our rooms which calculates room rates depending on the length of stay:
so the pricing model is like AirBNBlets say 20$ per nightIf you book 1 week, then the weekly price is 100$, if you book 2 weeks than the biweekly price is 180$ , monthly 350$so if someone books 8 days , i need it to calculate : 100$ for 7 days +20$ for 1 day = 120$
also they are not booking just the room but a package , we are a muay thai gym that offers accommodation on site and food. so they should be able to add or remove option :
-first they choose the dates-then they choose the type of room-then they choose how many session of training per day they want-then they choose to add food to the package
then they would be able to see the final price and a summary of the package that they have chosen, and an open comment box for their inquiry and a final button to inquire availability. This form will send an email to ask to check if we have availability.
Let me know if this function is possible and you can do it. Tell me the price and turnaround time.
Thank you!!