Originally Posted by Dr.NewEarth
The only thing I can suggest to weed out those unwanted character listed above is, don't use Craig's list.
I'm in the camp that really likes CL for leads. I firmly believe that as high a quality of an ad as possible goes a long way in people pre-qualifying themselves (read: weeding out) before they call you.
As a tip to filter out the telemarketers, display your phone number and email in an image. In fact, using a large image for your entire add allows you to tailor the visual exactly as you want, without conforming to CL's minimal html allowances.