To keep costs down I want to do the prep work myself. The back yard is all concrete except for a small 1x 2.5 meters which I would also like concreting. If the job would only be a couple of hundred I would pay to have it done, but if its much more, I could probably do the prep work. Any ideas on cost for this job and what is the best method to get the area ready for concrete, such as depth to dig, agrigates. The soil is also mostly clay under the little bit of top soil.