There are four LFS's I am familiar with besides petsmart.
Store A(exclusively fish): is located within a block of my house, I could literally walk there in less than 5 minutes. It only carry's the same fish that petsmart would sell, and since it doesn't buy in bulk like they do, it isn't able to get their fish as cheap therefore they have to charge more than petsmart. I have only been to this store twice, despite its close proximity.
Store B(fish, small mammals, reptiles, amphibians, birds, bugs): is about 20 minutes from me, but located near my grandmothers and sisters house, so I am around it almost every weekend, yet I never go their. They sometime have some rare fish to, but the tanks are always dirty, and the prices for common pet smart found fish are yet again higher than petsmart. I have been to this store a handful of times, but have not been there in over 6 months, despite its convenience.
Store C(Fish, Reptiles, Amphibians): is a good store, I make the 45 minute trip to them about once a month. They have good prices on dry goods and there fish section is huge. However there fish prices are pretty high compared to others, but they often have fish others do not, also only ever seen 1 dead fish there, and it was removed before I left (i didn't tell them). Only found this store about 4 months ago, yet have been there 10 times so far.
Store D(exclusively fish & Amphibians): This store is the best, and was packed with people, yes a LFS that is crowded. They carry all the basic fish, but I noticed they carried the color varieties the petmarts dont carry (pretty smart), also they specialize in rare/uncommonly seen fish. This store was packed with tanks from floor level 4 tanks high, had most of the fish I've only seen available online(and even then they usually say out of stock). Tanks were clean, fish were healthy and reasonably priced. They even pack the fish with O2. I only just discovered this store, but It is now my #1 store.
These are some factors I would take into effect:
1: Variety/exotics, I have noticed similar threads stating to start with "bread and butter" fish. I disagree. I know that I would not make a special trip to a store to get the same fish I can get anywhere else. Get fish that are uncommonly seen and that will give people the "wow" factor.
2: Cleanliness, keep the tanks clean, water parameters in check, and remove dead fish promptly. Also keep the shop clean, don't let the shop smell like Massivore, lol.
3: Display Tanks, I know seeing the huge display tanks my favorite 2 LFS's have always gets me in the mood to buy some fish, also gets my gears turning on new tank ideas.
4: Customer Service, Hire outgoing people. To me prior fish keeping experience is nice but not necessary, they will learn about the fish before long. Don't hire or let employee's get away with standing around avoiding customers, they is nothing more annoying than trying to track down an employee to bag a fish for you.
5: Visual Appeal, I have noticed almost all of the fish stores, even the ones I like, have a basic 2x4 skeleton rack holding the tanks. Would be nice to see a place with a finished look in the tank section with pictures of the full grown fish next to the tank holding the fish. Detailed profiles with average-max size, preferred water parameters, healthy diet, temperament, compatibility, minimum tank size...This doesn't have to be fancy, could be handwritten on an index card, but it is a lot better than just a name written in marker across the tank.
Location/Advertising: People need to know you exist, one way is picking a location in a high traffic area where passerby's will see you. Advertising, via paper, signs or even craigslist, not only letting people know you exists but what your about.
