Okay, let’s calculate this. Sher has a certification from the Interior Designers Institute, which is a reputable institution. However, her location in Lake Forest, California, is not a major hub for interior design. Her skills in color schemes, space planning, and project management are in demand, but not as high as those in urban areas. Considering her education and certification, I'd estimate her hourly rate to be around $75, which is a reasonable rate for an interior designer with entry-level experience in the United States.