The biggest thing I can suggest is to ask for REFERENCES and make sure they give you phone numbers, not letters. Call any and all agencies and ask for a packet. You'll get tons of info.
Our agency was awful. They only give out letters now. A friend of mine once called their reference (yes just one) and they told her they wouldn't use them again! Also this agency has threatened to sue people for slander if they post how they were treated. I can't say much more (for fear of being sued, ha ha).
Others may have betters suggestions as I did it the stupid and emotional way (but hey look how it turned out?

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