A LLC is a "incorporated" business. It protects you and your private assets - your house,car,bank account. A "regular" business that is not incorporated means you personally and all your assets are on the line if you get sued for whatever reason.
A accountant is a great idea for any size business. You will forget something related to bookeeping. And at tax time these people are worth every penny.
That 6% sales tax is for the state you live in. You still have to pay state and federal income tax.
It is a pain to jump through all these hoops but you will glad you did.