I recently left my job as an employee at the cigar shop here in OKC. It was a fun job, smoking was considerably cheaper, you get dibs on new cigars, your in the loop. Plus you learn a lot about the business side of tobacco, not just the smoking side. All in all, if you are going to start your own shop you need to have someone on your staff who as worked in a shop before preferably managed one, to really get you squared away.
We are taxed on EVERYTHING tobacco, and you have to know your taxes, make sure they are filed correctly.
You have to know the companies and vendors of the cigar world to let them know you are opening and to come and set up accounts and things like that.
It really is a lot of work, but if it is done right the reward can be really good. I worked at another cigar shop before I worked at the last one, and they were making 150-200% mark up on all their singles.
Hope this helps.
Nate