Anonymous wrote:What’s make and model?
Without knowing much about your car, I would agree with PP and look at taking it to a different independent mechanic if you don’t have one you trust. I would not take it to dealer because they tend to overstate and overfix what is needed. A “rattling” suspension can be from many things, starting from harmless and up to something that requires more immediate attention.
Seriously. Depending on the type of car, the proper response ranges from buy a new one to turn up your radio and live with it.