I recommend having an initial talk with a broker if you're thinking about it at all.

The brokers I've met are happy to talk if you have a profitable business, even if you don't plan on selling anytime soon, and you don't have to sign anything to commit to them. They can talk to you about what you can do to prepare for an exit even if you don't expect that to happen for several years (and it might take you several years to manage yourself out of the business).

I personally liked the broker I worked with and recommend him.[0]

[0] https://quietlight.com/advisors/chris-guthrie/