Licensing only makes you liable to best practices and standards as set forth by the state.
You still need to look into some sort of bonding/insurance for liability. Licensed or not, you are still liable for damages you may cause. And that's assuming you are working the job solo. Employee's are a sure-fire way to get sued. Just imagine the fun you'd have if some guy fell out of the cieling, crashed into the datacenter, and was hospitalized. Lots of money would flow then.
