Design me a Product

I would require a gadget kind of piece to be designed. The following should be available - The gadget should have a microtransmitter which should transmit the GPS location which will be preloaded when the equipment is installed in customer's premises. So the challenge is only to transmit the request data from the customer. The following should be displayed in LCD screen, 1. Welcome Screen says "Welcome, <Name>" 2. There should be 2 options. "Buy a book" & "Sell a Book". 3. Once clicked on Buy a book or Sell a book - there should be 4 options to select (options will be explained later) 4. Once clicked on particular option, the options will be assigned a number (1, 2, 3 & 4) 5. When clicked on particular option and order button is clicked. The following should be transmitted. a. GPS location or gadget Number (which will be preloaded when the equipment is installed) b. The type of option selected which will be a number since each option will have a number assigned