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The going rate here in the STL for pouring a slab that size is between $5-$7 per square foot. When I was debating whether to go that route or with pavers, I had figured it would cost roughly the same amount to do the pavers myself as it would to have a professional come and pour me a slab. I opted for the slab as it just wasn't practical for me to spend a couple of days labor and not save any money.The bigger the slab you have poured the better price per square foot you'll get. I wouldn't be surprised if you could find someone to do it for under $750. That's how much it cost me for a 10 x 17 slab last year. He is my neighbors brother so I was able to get a slight discount. It has paid dividends for him as I have given him 3 referrals since then.