Analyze the current market. The size, scope, and vision of the art gallery will depend on what is already available in the city or town where the new art gallery will open. Rely on experts such as artists and members of the business community to assess the market for your gallery. Try to gauge whether or not a type of art you are interested in or knowledgable about is adequately represented by current galleries in the area. If not, you have a starting place for your vision.