Interactive map needed to aid tracking of capacity needs

I mange a network of 60 self employed sales advisors in 7 counties within the UK. these advisors make sales visits to customer houses.

Part of this job is managing capacity of each postcode.

Cartographic Design
I am looking for an interactive map that will allow me to track coverage within each postcode.
The purpose of the map is to provide a visual representation of the coverage available to me.

The map should allow me to
- Pin the home postcode of each advisor
- Highlight the postcodes advisors cover
- Calculate the capacity needs by comparing the data provided relating to advisors and leads known to be generated within each district and postcode.

The map should be dynamic as all details change regularly

Speaking through this project over the phone will be essential due to explanation required of some detail.