I have prior worked on writing driver for PIC series controller , for configuration of a vehicle tracking device over UART/RS232. I also developed command line based UI for configuration of device via PC. I have done keypad and LCD interfacing as well.
Having 9 years of experience working in MNC for clients such as Seimens, Panasonic, GM, you won't be delivered with 'code'. You will get a software -Layer architecture, Design document, source code, V&V, User Guide. The software developed shall meet fail safe criteria -inherent diagnostics, and recovery from failure. V&V shall be done for the project using remote desktop. I will need some more clarification on hardware part though. I have a few prototyping board and HC-05 BT module.
Please feel free to connect if you want to discuss anything further.