Do some research in your area and see what people are chargeing. It will vary from where you live than you can adjust your price as needed. Plus if your starting out as a one man or women operation your prices may be lower or higher than someone who runs with a 2 or 3 man crews. You will always have someone in your area that will try to under bid or price gauge your business, I see it happen all the time. Your quality of work will also make you last longer and be around longer than a newbie that doesnt know he is losing his shirt.