Builders are good at building but not paperwork. From experience, you would be hard pressed to find a tradie who is good at paperwork. I had a similar issue- my builder did not put handles on my kitchen and claimed I did not specify handles for kitchen. In the final inspection- among some other things…. I said I wanted them fixed. They locked up and walked away. Next day I dropped him a letter (before email was acceptable communication) saying I cancelled the contract and keep $16k owed. He called me within 20 minutes with keys and accpeting the cheque.
My advice:
1 It pays to know your property laws
2 ensure there are clauses in your contract to cover how things are to be handed over