Do Your Homework!
Always depends and that's usually why you put together a business case to answer those unseen questions. Game stores and any retail outlets require a considerable sum of cash up front for merchandise, so it's best to do your home work. The last thing you'd ever want to do is put $40k into a new business and find out there's no business around.
I would first seek out a copy of
"Business Plans Kit for Dummies" which helps you find out what the most important questions are and how to start answering some of them.
Probably the most important questions to ask are:
* Are there enough customers to support my business?
* What products should I carry?
* How much money do I need?
* When can I expect to make a profit
To find out about customers I would suggest putting together a survey and taking a poll at an upcoming local Sci-Fi/Gaming/Comic/Media convention. I did this when I was considering opening a comic book store, and I got a lot of great input on where people shop today and what they purchase. You'll need to contact the convention promoter to find out about cost of table and other considerations. The survey will help you answer the first two questions.
Also knowing your local area's retailers will help. Is the market saturated? Do the local retailers provide good service or complete product lines?
Joining or getting to know
GAMA - Game Manufacturers Association, the trade association most directly involved in game retailing, is a great source of information. If I recall, they run workshops a couple of times a year for retailers and may do one for people thinking about getting in the business.
Subscribing to
Comics & Games Retailer, another top source of information on things like contracts, dealing with wholesales, lists of top selling games, leads on new merchandise, and other tidbits.
Reading blogs of game store owners like
Behind the Counter on the RPGnet site gives great insight on what it takes to run a shop.
Most of all, give yourself time to answer a lot of questions before you jump in, maybe selling at a few local conventions before you open your store to get a feel for the business. You might consider starting a mailorder business first to build a customer base while not dealing with the overhead of paying rent. Finally when you do open your shop you'll have customers the first day.
When I did my projections on starting the comic store costs ran well over $80k the first year and I didn't see any black (profit) until the middle of the second year. Can you wait that long (or longer?) is an important question you'll also have to ask yourself.