dont pay anyone to do it ! go get yourself a few scaff boards .
Stand em upright in the area you want it to create a box , nail the edges together to stop the concrete running out and get the driver to fill it for you , all you gotta do is rough level it with a shovel then finish it with a length of wood by tapping it . probably only take you 4 hours start to finish ( you might want to dig out and hardcore or steel the base first if you intend to put cars etc on it tho )