Most of my illustration clients have been architects and planners. Usually interior imaging and conceptural illustrations are also from architects. 

Occassionally a call comes in from an artist for help in concepturalizing their proposed art space  or for showing lenders what they intend to do. 

A few illlustration clients have been real estate brokers that want help in conceptualizing a new look for their marketing offices. 

One client wanted to generalte a whole new idea for a sports venue.