when should you think about using a configuration management tool

So, I've been wrestling with how we handle app configs across all our different places and servers. Right now, it's all manual or just basic scripts, and honestly, it's getting messy as we add more stuff. When do you guys think it's absolutely necessary to bring in a real config management tool, like Ansible, Chef, or Puppet? Is there a sweet spot, maybe based on how many services we have, how many environments, or even how big the team is, that makes you say, 'Okay, time for a tool'?