It's a volume based business. If you are just distributing then you need to be even bigger than if you are just running a tap room.
The former requires a 7bbl brew house minimum and 15 - 30 bbl fermenters plus a brite tank per 4 fermenters plus so much work that it's all you'll do for 80+ hours a week. Investment will be between $250k and $500k depending on your local codes and laws. Break even is around 3000 bbls. The logistics mean this is completely a full time gig.
The latter likely requires (depending on local laws) rezoning for serving alcohol and a minimum of 3bbl brew house with 3bbl fermenters and brite tanks. You need to serve* around 250bbls to make money. Investment can be as little as $100k if you are lucky and that doesn't necessarily need to be spent all at once. Customers are getting pickier about the breweries they go to and things like location are mattering more and more every day. So if you are located out of the way you better be serving damn good beer, not just average homebrew. Also consider serving food the revenue could make life more bearable and attract more patrons. If you think this is a viable route for yourself then go get colorado boy's books. (other book) Tom Hennessey has been successful for a long time. He might not have the perfect way to do things, but it's tried and true.
*serve as in sell. You probably will brew about 300bbl to serve 250 assuming $5/pint.
Part time - it's a giant pain in the ass to brew beer and run a business. The only reason to do it part time and for as little investment as possible is to have enough revenue and business age to qualify for a loan to go bigger and/or prove the strategy to an investor (assuming you don't have $500k lying around burning a hole in your pants). If Florida's laws were more generous, I'd have gone this route a couple years ago. I already brew on a pilot system, I just can't sell the beer. I would probably already have a viable and growing brewery if that was the case.
Little math for you so you can run some numbers. You can fill a fermentor 17 times a year on average. Go from there.