If memory serves me correctly, aren't the more affluent and populated areas west of downtown Phoenix but south of Glendale?
The most affluent municipality is Paradise Valley, which is in the northeast, surrounded by Scottsdale (also an affluent municipality). To the south of Scottsdale is Tempe, where Arizona State University is located.
The southwestern part is… well, Buckeye, so not really. Or Laveen (technically a region of Phoenix proper), consisting mostly of… dairy farms.