Senior Design Project: Wireless System... HELP!!!

I am currently working on a senior design project for next semester and need some help. The objective of the design is to take a wired barcode scanner and convert it to a wireless scanner that can communicate with a PC. The range must encompass the size of a typical house. The scanner has an rj45 male plug connected to a USB converter. The signal on the USB has a frequency of about 70 KHz. Here is a link to the scanner:
Metrologic Instruments Inc. | Products - MS6720

Also, the computer must be able to transmit an audio signal back to the computer. I have limited experience with wireless hardware and have come up with few feasible solutions. Our budget is $125 dollars (the scanner was provided).

We have currently designed an audio transmitter, just below the FM range, but cannot come up with a good solution for the barcode scanner transmission. From what I have read, it seems that we will have to transmit in the 2.4GHz band, but I don't know what technology to use. It would be nice to implement both the audio and the barcode transmission into a pair of transceivers: one at the PC and one at the scanner. They will never be transmitting at the same time. There could be a relay transceiver in between the two others...

Any ideas or comments would be greatly appreciated. Thanks.