I liked that you picked a service that has a relatively low barrier to entry. The real asset are local operators and referrals. Making them more efficient without being controlled by a big company would be a boon for everyone involved.
Consider being a platform coop with regional operators as members. See https://platform.coop/
I’ve never heard of platform Co-ops. Cool! Lots of people predicted that a beloved local coffee shop was doomed to fail when the workers got a loan and bought it to run as a completely flat cooperative. It’s been a few years and they are absolutely killing it. I’d love to see the tech version of that.
Yes, the barrier here is the desire to study and pass the exam. If willing, you are up and running relatively quickly - but only as a technician under someone else's operating license. To get the operator license (eg to be a full on pest control company) requires 2+ year documented experience and another set of exams.
The operating license holder is also on the hook for legal action if (when) things go wrong.
"Control" is interesting and I have found in all trades that people value their freedom. The good companies don't monitor employees too tightly, and are rewarded with loyalty and longer tenures generally. Of course you have to run a good recruitment and referral process to find the good people!