Shawn Culhane has a pretty basic game plan: Find clients and make them happy. “If you can do that, success is pretty much limitless,” he says. Culhane, 27, entered the business in 2008, just as the economy collapsed. But the entrepreneurial feel of real estate was irresistible, so he turned the tough market into a personal challenge. “It actually feels a lot like poker. It’s all about taking a calculated risk.” That might mean going into debt to buy online ads or setting up eight Web sites with in-tegrated lead capture tech-nology. This year, he’s doubling down: Culhane, a successful caddy in high school, bought a mem-ber-ship in an exclusive Austin golf club to attract high-end clients, and soon he’ll begin construction on a $1.3 million spec house. A client who hired him because of the golf membership is a potential buyer for the spec house. Jackpot?