What hardware am I going to need

Hi. I’m trying to setup a system which seems complex to me, but maybe simple to you, any help would be appreciated.
My goals is to set up a system with multiple operators running out of their home(no office) the goal here is to have the customer click a call now button and my asterisk based server will call their phone (cell phone or landline) and then connect to the operator (cell phone or landline). The order in which the calls are placed isn’t a big concern to me. I would also like to have them billed in real time(pay per minute). My question to you is what type of system and hardware am I going to need. The goal is to have an 800 number and each operator will have a separate extension
Example:
John Doe ext 274
Jane Doe ext 275
So if John Smith wants to call John Doe, he will open his web page and John Doe has a call now button. In which case John Smith clicks it, his phone rings from my 800 number and it connects John smith to John Doe.

My explanation may have made it sound more complicated then it is, but any help would be appreciated. Thanks!