Boss Hoss
FRF Addict
Autogeek.com has a hard water filter that hooks up to your hose bib that filters out the hard water. We have hard water that leaves nasty water spots too so I got one and it eliminated the spots. Costs about $100 and just attaches via a short piece of hose (which is included with the filter) to the hose bib. If you get it, note that the filter does not come with a hard water filter, only a sediment filter, you have to order the hard water filter separately. The filter is easily recharged. I now leave it hooked up to the one hose bib and my wife uses it all the time for other things too.
Ding Ding Ding!! We have a winner. Clay Bar for water spots--not good. Leaves the paint Nekid!!!!