Medical software for clinics conducting pre-medicals

I'm looking for a medical software solution to streamline the administrative and clinical operations of clinics that conduct pre-medicals. The software must provide efficient electronic medical records, along with the ability to schedule appointments and issue invoices and bills. It must also integrate with medical devices used at these facilities, and run on a Windows platform. If you think you have the expertise to develop this software solution, please let me know about your availability. Thank you!