Desktop support

This is a behavioral health Clinic in Reton, Virginia. We have .. desktop computers and 5 printers. I want someone who can do followings: 1. Install and Update security software 2. Maintain computer to keep them at the best possible condition. 3. Troubleshoot and fix minor networking issue. 4. Take call from office staff and resolve issue as it arises. 5. We have Panasonic TDE 100 BPX system. Any knowledge of this system is a big plus. This will be an ongoing contract.