I just checked your profile and you're on the left coast, but there are a couple of ads for brokers in the current issue of SpinSheet, a Chesapeake Bay sailing mag. One in particular specified prior sales and service experience of any kind, so you'd qualify for that one. Good luck!
Oh yeah, there is an association of yacht brokers that does certify people. Can't recall the exact title, but surely someone on here knows about it.
I recently retired after 37 years on the job and I have to say I have not considered two second careers you read about retirees pursuing all the time -- surveyor and broker. Both seem pretty well staffed as of now. But that's just me.
(The wife of the marina owner where I keep my boat did tell me that if I keep hanging around there she will give me some sand paper and a
paint brush when the weather breaks and people want their bottoms done. FYI -- I didn't go there at all last week, but will go tomorrow. I'll stay out of the office so she won't see me.)