Looking for Call Monitoring Tools for a Small Sales Team

I run a small operation with 9 employees handling sales and support through company-provided SIM cards. The challenge is that I have no real visibility into what's happening on those calls—call activity, follow-ups, customer history, the whole picture.

I'm weighing whether to build something internal or find an existing tool that already solves this. The business need is clear: we need to track customer interactions without relying on people's memory or scattered notes.

Has anyone dealt with something similar? What tools or approaches have actually worked for a team this size? I'm curious whether call analytics + CRM combos exist that don't require enterprise budgets or months of setup.

Any recommendations would be appreciated.