Phone Number List Management

Phone Number List Management

I'm trying to do a couple of things

1. Be able to set the "best phone number" by checking a box or automatically designating the newest entered number as the "best phone number."
2. Have a field that automatically tally's the number of fields with value (if phone 1, 2, 3, and 4 have a number in it, the field will automatically show "4"), akin to the COUNTA or COUNT feature on excel.

Thank you!