Its all well and good as a hobby, you brew when you feel like it, no deadlines to fill and brewing what you like and want to drink but seriously think this one through..
Say that you need an income of £30k/ annum and you can sell a cask of 9 with an ABV of 4.3% for £60 or so. The maths are that with ingredients, leccy, beer duty, you would be lucky to achieve 40% as a mark up.
This has to pay for, rent, fuel for the obvious van, insurances, breakages, mainainence, upgrades, purchase of kit and return of capital to backers, replacement of casks and your income etc
so say rent on a lock up unit or similar £400/month, fuel for van £200/ month, insurances for stuff £150, £200 for maintainence, £100 for upgrades, then if you have to borrow funds to set up, the costs of that on top.
You will need to shift a lot of casks, just to cover the costs, then to make a few bob will have to shift at least 20-30 casks on top each and every week
Therefore the set up that you will need has to be at least able to kick out that little lot, also how many times will you brew in a week?, once, twice if three times is your answer and then you will be falling short of deliveries, losing track of casks, getting in a muddle with the paperwork. HMRC are gits and do not like to know that you are not up to the job
I have looked at this seriously as a 2nd string to my dayjob. I would need at least a 5bbl brewery to accomododate that little lot, brewing twice a week. I think for the first 6 months or so it would be an adventure. It could be great but the capital employed to do it properly is daunting.
However I think the best idea is to buddy up with a micro, take your best beer in for their opinion, offer to help for free. Then if your really lucky and they are impressed with your beer they may offer for you to "cuckoo" with their brewery, Google "steel city brewing" for your insperation