Mark and Marty Brown are nationally ranked, top 1% real estate professionals who have spent years doing what most agents never bother to do — deeply studying the condo market. That obsession led to the development of the CS Index™, a proprietary scoring system that analyzes every building across three key metrics to predict how fast a unit will sell and what it will actually fetch. No guesswork. No generic comps. Just data-driven precision built exclusively around condos.