Most likely the least expensive part of the deal would be the stud fee. It might save you a few thousand to have it waived, but buying a mare (whatever you want to spend--$2k? $20k? more?), boarding her, vet bills, insurance... ain't cheap
I'm on the opposite coast, but combo stall/turnout boarding for a riding horse here is around $600 per month. Depending on facilities and location, pre-foal you're looking at maybe $15 to $30 per day for broodmare boarding. Vet, farrier, foaling expenses, and care for the baby and eventual boarding for the little one too once it's weaned.
I guess it depends on what the goal is, too... breed to sell, breed to race? Would you keep the mare after she foals?
Lots and lots to think about, and you've gotta have a bit of spare change to cover regular costs plus random vet bills. I know there are a bunch of people on here who can give you specifics, but that's my input. I've never been involved with breeding, just yearlings and horses in training, so this is just my take on the whole thing... because I
do daydream BIG when I browse the Keeneland catalogs every year and I'm a pedigree junkie
