Originally Posted by PsyDoc
Well, if you already have the hard water spots on your car, then I'd go ahead and find out who the best car detailers are in your area. Perhaps even go over to the Meguiars forum and get some recommendations. Once the water spots are gone, just keep a good coat of wax on the car (wax it 1-2 times a month) and try not to let any water from your hose or sprinklers dry on the car. Over time, the sun can "bake" the minerals in the water into your paint and you might not be able to completely get rid of them. If you want to tackle the job yourself, then the products are there for you to do it but expect to take the better part of a day to do it right.
I love Meguiars! They even have the "how to" videos on their site that are very helpful. Order from them all the time.