Wedding coordinators can be an invaluable source for advice, expertise, and general calming-down-of-your-nerves when planning a wedding. The good coordinators are gems, and are well worth the price to hire one.
Problem is, they're not all good.
I blame television for the sudden influx of so-called wedding planners into the market. It looks like so much fun on the shows, so people think "hey, I could do that!" They charge you very little and deliver exactly what you paid for. They also make the job of the professionals who they're working with more difficult since we have to deal with weirdness from them, and do damage control with brides who are confused because of them.
I had someone call me and tell me that her coordinator included pickup of the wedding cake in the services that they offer, so that I wouldn't have to deliver it. Uh, no, that's not going to happen. Unless I know the planner (I'd never heard of the guy) and there's a REALLY good reason, I'm not going to let someone pick up a wedding cake. There are too many things that could go very, very wrong. I'd never heard of that particular "service" before, and I know that the planners who I work with would be horrified at the thought of picking up a wedding cake when they're in the middle of the wedding day events.
I've had planners who refused to give me the contact information for brides because they say that they're the gatekeeper for all of the contacts, payments and appointments. Well, guess what? My client is the bride, not her planner. Having a go-between makes everything more difficult, and it isn't the planner's job to make things more difficult, or so I thought. Again, the reputable planners who I work with wouldn't think of withholding information from the vendors they work with. I've actually had potential clients who I wouldn't work with because the planners were so difficult from the first contact.
So when hiring a planner, make sure that they have a good reputation and have been in business longer than ten minutes. If you're shopping around and are finding prices pretty much the same, then find one person who costs half as much as everyone else, don't celebrate yet. (This is good advice for everything, by the way, not just planners. For services from wedding to housepainting the lowest price isn't always the best deal.) Do your homework and make sure that you're not going to get half the services and twice the aggravation for that low price.