You would invest in a sales techstack, like HubSpot or Salesforce, or something similar to enable the BDR to maintain high levels of call activity, multi-channel outreach, and to include reporting you would need as manager to coach.
The BDR is assumed to be working full-time for your MSP.
Other sources for building the model include Salary.com, Glassdoor and The Bridge Group.
How to get a Copy of the Calculator
Since some of my competitors visit our site, I'm not putting the calculator up for anyone to download. Instaed, just email me from your MSP email address and add subject-line "send the ROI calculator" and I'll reply with a copy. This will be manual to start unless my inbox goes crazy so please bare with me.