Audit Process for The REC (Retail Energy Code) and MEM's (Metering Equipment Manager)

Hi

I am an Electrical contractor working in domestic properties and we are looking to expand our services into installing Main switch isolators between the meter and consumers installation. 

I am working my way through the application process with The REC (Retail Energy Code) to become a MEM (Metering Equipment Manager) to enable us to install main switch isolators. 

Has anyone else been through this process and can share some advise?

regards