Just don't. I got on their list by attending a high-pressure timeshare sales event for fun. It was fun and I highly recommend it for the entertainment value (mine was in San Dimas, CA), but for the love of gods don't give them your actual phone number.
It's now three years later and I still get phone calls, half of them immediate hang ups, all of them from an 818 or other southern California area code. Telling them to stop doesn't work.
Sometimes my bitching on Yelp will yield a call or message from a corporate-type, the shambling, dead-eyed Camaro drivers who I imagine watch menacingly over the chirpy Filipino call center workers who solicited me a week prior. Generally they assert that it couldn't possibly have been their company who called me (I've taken to asking), and if it was it had nothing to do with the high-pressure timeshare sales event.
Last note -- I did get a few free to discounted travel offers from attending the sales event. They proved so impossible to use with restrictions applied that I, infinitely flexible and critically cheap, didn't even use them.