Some agents may disavow Craigslist; especially since social media giants Facebook and Google+ are basically taking over the world. But many experts are saying: not so fast. Agents and brokers should give this old dinosaur a chance. Amy Gerrish, leader of The Phoenix Metro Group, an agent team part of Phoenix-based HomeSmart, says Craigslist seems to offer a better return on investment than advertising on listing portals or Facebook. The…