On craigslist I find it's easier to email first and wait for a reply before calling just to even confirm the number. Also can find out alot of interesting things by the response. Usually if it's worth calling to begin with.
As with CL or any other ad; user beware. I always use a cell phone, and/or email that doesn't display my last name. (i.e. use hotmail, yahoo not your personal email)
I recently met someone, who now thinks we're more than friends. We could never have a long term relationship because his financial life is unstable. I have to keep making excuses to not see him. He's gullible enough to believe my excuses and keeps calling. I had a friend answer my phone the other night, he swore at him and told him he's my boyfriend. (NOT)