I run (and have run) several businesses. I've never had a business license. Depending on your state, some states require a
"seller's permit" if you're going to sell at an event so they can keep track of sales taxes you owe them. You can contact your state tax commission for information of sales tax collection.
The best source of information business entities is to contact your state secretary of state's office. They handle all of that sort of thing. I recommend getting an LLC for most small business scenarios. Sometimes just a DBA is enough. Neither one is expensive or hard to do. Your secretary of state office will handle both.
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