Shelnic kitchen and gas -Worst customer experience after paying in full not finishing job:(

Worst customer experience I have experienced!!Very sneaky and full endless excuses to come back to customer and finish off as per agreement after been paid in full , paid owner of the company in full 2 months ago before he started ,he promised it is just a day job fitting guest loo cupboard connect gas line to stove and fireplace and putting a slab underneath gas cylinders , its been 2 months he only came once .I also battled with getting company guy to come and issue COC after gas connection . I had to inform him that estate body corporate and insurance requires it then he eventually came. There was a problem with the gas stove flame strong blue lights my pots were black. He advised that appliance technician should come. Appliance technician had to call him ,wanted him to explain how he issues COC for gas stove fitted with wrong nozzles for air instead of gas cylinder nozzles since in the box they pack 2 nozzles gas cylinders and air.Technician changed air nozzles to cylinder nozzles for us and flame was ok .when we advised him he was argumentative and defensive .He has now disappeared into thin air ignoring our calls .We still have issues with kitchen high gloss soft touch cupboard doors he fitted year ago they don't close properly .My mistake was to be too trusting paid him if full he ripped me off my advice don't pay him anything until he finishes what he promised. He took advantage of me.