Rutwad -
Since your machine is classified as a "forestry' machine on the ASV website, you may want to consider checking into whether or not your state has approved/recommended vendors for your services. If so, get signed up.
I know I looked into approved vendor list on the NCFS website when dealing with forestry issues on my property. Also, maybe you want to get your license so you can use chemicals that will stop the regrowth of the materials you are shredding. Some of the machines out there like the Brown tree cutters, are sold with an optional herbicide introduction kit, so you get a one pass does all effect.
If you are looking for a place to gain some experience, and don't mind traveling to WNC, or considering a lower hourly price, send me a PM -
Regardless of the later, good luck in your new business venture