I am going to assume you are working from home since you are asking this question...Your business address can be anywhere that your business can receive mail. So, if you have an office, use that. If you have a friend with an office, ask if you can get your mail sent there. A more legit solution may be to get a Virtual Office at one of the many shared spaces popping up around your town. Usually, these co-working spaces will have a "virtual office" option whereby you can pay a monthly fee and use their address for your business, get your mail forwarded, and get discounts on conference space.