Has anyone hired dancers?

I was wondering if anyone has experience with hiring dancers to liven up the crowd. I assume this can be done through some of the DJ's. I am trying to plan a surprise - a mini- flash mob maybe 5 - 10 dancers. Any idea on how much something like this will cost?

My mom hired dancers for my Sweet 16. I don't remember them getting the crowd too hyped. My opinion is save your money on dancers and put it towards an amazing DJ or band. It's their job to get the crowd hyped!!

On the other hand, if you want to do a flash mob, that's different. I don't have experience with dancers in that respect.