Job Blacklist?

I’ve just been contacted by a member complaining about a guy he contracted through the forum ( not delivering his work as agreed. I’ve seen this happening a bit too much lately, so I was wondering if a blacklist would be a good idea. It would require us to deal with lots of whining though, like in the conflict DDD recently got involved in. I’m not sure if a selective ban from the Jobs forum would be a better alternative, but I think exposing the members would make a better impact than just banning them from it.