VOIP Setup for Business Communication

I'm looking to have a 3XC VOIP system set up for my small business. The system will need to accommodate 1-10 users, with potential for expansion in the future. While I haven't specified essential features, I am open to recommendations based on common business needs.

Please provide:
- Your experience with setting up 3XC VOIP systems
- Any suggestions for essential features based on typical business use
- Your ability to ensure the system is scalable for future growth.