Hi, Sean - I think a good way to start would be to ask some pet shop owners in your area for an "information interview". That means you get an appointment with them, and ask them about starting and running a pet shop. That way, you learn from experts.
You will get all kinds of business information that way...how much it will cost, what licenses you have to have, and other good stuff! Plus you get to visit all the pets.
Let us know how it goes.
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