Hi,
I am Bryant, an experienced freelancer with good reviews ( http://www.freelancer.com/u/bryantandk.html)
I've just read through your requirement and sure to let you know that I am glad at extensions development.
Your price for this is about $250, but I think $300 is a reasonable price with better service.
Hope that you can give me a try or can we have a further conversation on this project?
Thank you!
Best regards,
Bryant