Johnny,
I agree with the earlier comment. The devil is in the details of course as to how rigid you are with some of the requirements and how they function and it boils down to how many hours of development an individual developer thinks he/she will spend to implement it and what they feel is fair for that amount of effort. For quick responses you might be better advised to just disclose what budget you have available if it is small in particular and get responses about whether anyone would be willing to tackle the project at your price. I can tell you a few considerations I would keep in mind in such a venture is this:
1) Any estimate is going to based on a combination of what modules might be available out of box. The quality of those modules and maturity should be evaluated as well as if they are something that has a history of good support by the vendor. Unless it is open source you will be tied to the quality of your module vendors
2) Streaming live video is a different function than just dropping a bit of code on a site. It typicall requires a content management server and some technologies behind it. Likely you will integrate a function on your site but really that content would come for a streaming video provider outside of the DNN site you develop.
3) Take the time to pre-generate your content for the site before you engage your developer so you can focus on rolling out the site and don't fall in a pattern of on again off again development that I see often where you are really the bottleneck and the site has to be redone when the actual versus expected content is delivered which ulimately costs more money
4) If you aren't a technical person be careful in selecting your developer because likely you'll want to have someone you can call back in the future and support you.
Gut feel .. the DNN related functions won't be that hard but build in time for selecting a host provider, deploying the site, figuring out the streaming video (I'd recommend that for a phase 2 deliverable.
If you would like more details on a quotes etc. for the work feel free to contact me.
Thayer Tate
VP, Project Services
SolTech, Inc.
thayer.tate@soltech.net
404-601-6000 x284