In total, the average cost for an installed sprinkler system is around $3,150 or $0.60 per square foot. The cost will depend on the service installing the sprinkler, what kind of system you want, and the size of your yard. ● The typical cost for a ⅛ acre is between $1,000-$5,000. ● The average for a ¼ acre is $2,000-$11,000. ● The cost for a ½ acre comes to $4,000-$20,000.