Will shortly be laying about 5 c/metre of concrete in new 7.5 x 5 metre garage, there's steel mesh reinforcement (I had some left over). It's too wide to use a straight edge from one block (at DPC) to the other so do I just go free hand with a wooden tamp and trust my eye or is one of them concrete floats worth renting (about £40/day). Or is there any other way to achieve a decent level surface ? Thanks in advance.