Decrypt proprietary mag stripe fare card - repost

my company is currently evaluating a bid to compete for a contract to provide proprietary magstripe encoding for a municipal transit system. We are looking for someone to reverse engineer the current fare cards system since it is proprietary but will come off patent by the time of award. We are seeking your help in figuring how to read and write to the current technology so we can make improvements and improve our bid. The currents system uses a read write redundency to matain a stored value on the card whichis reduced with each swipe. you would have to develop the means to read the tracks and to write to the track. The main purpose of maintaining the technology is to contain the cost of installing new readers if the card vendor was changed. please contact me so we may discuss this further