Solution for “recommendation services”?

Hi,

I am looking for a way to implement such solution to WordPress based site (no real site yet, only design stage):

Site contains two user groups: “Requesters” and “Providers”. Website visitor can register to be either “Requester” or “Provider”.

“Provider” creates a profile and lists his/her capabilities, interests, bio etc.
“Requester” creates a simple profile.

Website shows a list of registered “Providers”. “Requester” can select one and make an order.
An order is for recommended Movie OR TV series OR Music OR Books list based on criteria “Requester” specifies.

When order is submitted, “Provider” gets notification about it and goes to his/her account, takes an order and starts creating a list for “Requester” from predefined list of items (movies, TV series, music, books). When done, sends completed order back to “Requester” with a list of requested items.

“Requester” gets notification and can view the list in his/her profile.

This whole concept might be similar to an eShop for subscriptions or downloads with multi-vendors, but the thing I can’t think of is:

• How “Providers” can fulfill request after order is submitted and send response back to “Requester”?
• How “Providers” can make predefined list of items in their profile which can be seen only to them and used when filling in response to request?

Thank you in advance for any ideas or suggestions.