Flash Webcam site that can grow very large without breaking

I need a webcam style website built. It should have have a pay per minute type of billing system built in, preferably by purchasing 5 minute blocks of virtual credits or tokens. The billing system HAS to be secure, and not some text file. Paypal billing through the site is fine. Must be able to expand to hundreds or even thousands of users at once (as long as we upgrade hosting to handle the traffic. Just make sure the system will handle expanding that far) It needs to be Flash chat, with audio and video with little to no latency in the communication stream. Needs to have performer profiles that populate the profile as the performer adds info to the different fields, and all this tied to and populating a set of databases based on categories and subcategories. For example, if a performer is an A and does Q and R, and another is a B and does Q and X, those categories and subcategories should auto-populate and be searchable from a dropdown menu. Needs to have control panel where I can log in and set what can be entered or asked for when a performer completes a profile and where I can activate/deactivate a performer. We have design set already. Completed code will be placed inside design by us, so no need for design work or implementation into design.