Three pieces of advice, as someone who has owned a "craft" business for a few years:
1) don't underprice yourself just to make some sales. it's very hard to raise your prices later. so find a price point you feel comfortable with and don't budge.
2) don't over do the design. find a way to make the product in an amount of time, with a material that allows you to charge a price you're comfortable with. don't skimp on quality, but maybe dial back the intricacy.
3) maybe just find a way to sell enough to where the hobby pays for itself. if you can sell a few items here and there that cover the costs of your materials and tools for personal projects, that is a huge bonus.
also, Boriqua is dead on on all points!
NOTE: my business is not in leather work at all, i'm a novice leather worker at best.