How big ( max gallons) and how much money did your existing brewing set up cost. Let's keep this separate from fermentation chambers and dispensing kegerators and Keezer systems.
My Zymatic makes 2.5 gallons. When I add in a stirrer, a chiller, a grinder and misc flasks and fittings etc, i think I am around $2600. And that does, by default, include a 5 gal fermentation keg.
Not a contest of cheapest or most expensive. Just curious.
I can make 15G batches, but usually it's 10G.
Hot side: 20G pot with a ball valve, about $120. Propane burner, about $60. Immersion chiller 50' (made myself), about $50. Coleman 70qt cooler mashtun, converted, about $60.
So probably $300 on the hot side.
EDIT: I forgot the cold side, I have 5 large fermentors (6-7G), and 5 3G fermentors (nice for splitting batches). All were about $30 average, so that's another $300 in fermentors alone. Refractometer, hydrometers (I have 3 and I broke 2), starsan, mineral additions, fermcap, tubing, winethiefs, bottlers, siphons, caps, airlocks, stoppers, wing capper, bench bottler, bottle cleaner, oxygen stone, oxygen tanks - it all adds up quickly. Oh, and brewometer. So maybe another $400?
My biggest "investment" by far is on the cold side (serving). Keggerator, kegs, gas cylinders, regulators, connectors etc. - I have probably close to $2-3K tied up in that.
20G CO2, 5G CO2, Nitrogen tank, two regulators (CO2, N2), 10 kegs ($35-40 or so each), 8 lines/taps with all sort of connectors, 8 faucets, (probably easily ~$60-70 per tap line, times 8) etc., fermentation fridge ($100), keggerator freezer ($300 plus collar, another ~$50), both with temperature control (~$30 each), additional heating belts/heating elements, various random buckets etc etc.