I have an idea...Orijen dog foods are amazing! Homemade, gourmet treats are also a big hit, fancy dog bowls, DOG CARSEATS, etc. Things that most people have to order online, a lot of people would prefer just to get it in a store but can't find it (me included).
I also dream to open a pet store and when I do, I hope to have a groomery and pet cafe, too. Of course that is many, many years away