I'm not an IRS expert, but I know a little after being an IC for almost 10 years.
First, you don't have to have a business name unless you want one. A sole proprietorship is a lot simpler than incorporating, which is fine for a sole person operation. You need to check with the State and your local municipality about a business license--they aren't required in my state, but they could be in yours. You don't have to be insured, but there is omissions and errors insurance. I don't know how litigious Florida is.
The employee/IC for the same company is a tricky issue because it might be difficult to differentiate between employee/IC status.
There are no specific IRS rules for MTs, but there are tests to determine whether one is an employee or an IC. Your state might even have more stringent rules (mine does). Check out www.irs.gov
and search for independent contractor and see what you get as far as their rules go.
Hopefully someone else knows more about this than what I've picked up along the way!