It wasnt my business, but I worked heavily along my sister in her aquarium/fish stores. The easiest part is actually the day to day operation. The behind logistics are what kill you. Supply, taxes, payroll, leases, competition, etc. The biggest take away I saw, and the thing that saved my sister during her divorce? LLC your shit. If you keep your name on the business, your liable for fucking everything, including stupid shit like frivolous lawsuits.