If I have more than $1500 invested in my poverty biab setup I’d be really surprised. Even if it was 2k with bulk grain buys and bulk hops sales and reclaimed yeast I’m making 5 gals of simple delicious beers for $12-$15 per 5 gallon batch. Consider the cost of two 30packs of labattes is $40 and I can brew a pale ale that will taste better for $13/14 that will be really damn good and get 53 beers. That’s 1.3$ per beer buying vs .26 cents per brewing. I’m saving a buck a beer. After 25 kegs or 125 gallons it is now cheaper to make beer because my equipment is paid for. That’s using cheap store bought beer most people who would say” you don’t save any money” would be drinking anyways. When you move into hoppy ipas and stouts , Oktoberfest, winter the savings go up compared to commercial. I’ve hit the point where people actually keep drinking my beer instead of drink one to be polite and go back to cans. Essentially I’m making good beer for cheap.
In your example it takes 70 batches or 351 gallons to make back your $1500. I’ve ran the numbers on equipment and in my opinion $1500 dollars is not reasonable for the kind of equipment you would need to make that much beer.
The margins in craft beer would be better, but your costs would also go up. Using your numbers it would take around 150 gallons to break even.
Even though this would be a labor of love, that much beer would be a lot of work. I figure around 100 - 200 hours. I really don’t think you can completely discount that amount of time, unless time is to you a not valuable resource.