I have already 7 enterprise customers, and now I’m getting somethings about 3-4 leads per month. That’s not a lot but I’ve realized that I can’t handle it by myself.
So you need one salesperson, not a manager. Not knowing how much profit each customer generates, you need to do your numbers. A good rule of thumb is that a salesperson needs to generate 3-4x profit / customer for their commission and their anticipated annual commission would need to be at least 2x what they could earn in a "typical" job for that age, knowledge and experience.
Especially with enterprise customers - ultimately, each can be as productive a pipeline, even moreso long-term, than an individual salesperson.