Spend some time looking through the post. A good deal of info is shared in those post. My main income is from home repaints. You will need to take a look at your area for commercial work and what the market brings. If you have a contact or two who manage commercial job sites, invite them to lunch and ask what the going rates are for the type work you want to do. I believe you will get a good feel as you read over the various post also.