When working with a contractor, don't make final payment or sign an affidavit of final release until you are satisfied with the work and know that subcontractors and suppliers have been paid. State lien laws may allow unpaid subcontractors and/or unpaid suppliers to attach your home.
The problem: you don’t have a mortar box or wheel-barrow to mix up those small batches of concrete. Instead, use the ring method on a slab or sheet of plywood. Put down coarse aggregate on the bottom, followed by layers of sand and cement. Reserve the center for a mixing well. Then add water to the center and pull the ingredients into it with a garden hoe.