Nowadays these systems are called UCaaS (Unified Communications as a Service) since they integrate with other systems. I've personally used Dialpad for their call recording and AI transcriptions, Ring Central is popular and has call trees, then you have things like 8x8 if you're going for more of a call center vibe (which it doesn't seem like since it's only 8 people). Feel free to DM me if you'd like any intros to any of these vendors - Ive worked with them before and happy to connect you directly to the right people.

I've used a litany of VOIP solutions over the years and it is so varied that the only recommendation I have is to try one or more providers before committing to anything, especially a long contract. And be sure to read the fine print on cancellation policies and such as many haveredactedday notice to cancel before you're auto-renewed. I have experience with Zoom, Ringcentral, Zoho Voice, FreedomVoice, 3CX, Dialpad, Verizon FIOS, ATT Uverse, Nextiva, and countless others. There are dependencies on your geographic location, ISP, network equipment, etc. Some of which is not under your control. I always try to work with my ISP for VOIP so I have one throat to choke ;) and minimal finger pointing. And make sure you're savvy in number porting ;(