The only proven medication to reverse skin aging is humble, generically available Retin-A (or other retinoids). Surgery is available only to the rich, but that carries the risk of winding up with a strange, uncanny valley face.

edit: I really attribute more of the difference in appearance between rich and poor as due to lifestyle as opposed to any fancy spa treatments. The poor are more likely to drink more, smoke more, and be overweight. I imagine sunscreen use is much lower as well. All of these factors absolutely do contribute to poor skin.