Job opportunities at an organization may use several agencies to post their ads. You'll notice this by reading the job descriptions as agencies compete against each other and postings are exactly the same, just different agency.
I personally had a bad experience with an agency where they called and scheduled me for an interview. I showed up to the scheduled meeting and the recruiter told me that the position was already filled but wanted to get more details on me to add to their database....They could of at least called me before hand or sent an email that it was filled.
Also, watch out where you send your resumes on craigslist because you never know who is looking at your information. If they don't post a valid company email address or domain website, I usually avoid those ads. No way I'm sending my resume out to
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