I charge at least $50 / hr, usually more. Sounds like this would take about 40 hours (1 week) of work to write both client and server code, set up a box with everything running, debugging, etc. That makes $2,000. Then I would charge 1.5x for the usual extra crap / requirement change buffer, to make it $3,000.
Then again, I'm a professional living in the San Francisco bay area. It's absolutely not unheard of to charge $100 / hr or even more on that, depending on the field.
I would recommend doing it yourself or going with a library like
Game Gardens.