I wax my car weekly. Have done so for years. Never had any problems with so called wax build up or yellowing. All my cars have been black. I would not be concerned about over waxing. Especially in Sunny Florida. As you know the sun is the biggest culprit in paint damage. So keep the wax on and enjoy. Try this, I have used it for years. And yes, better than Zaino.
www.malms.com
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Anthony M. Morrongiello