He can register a lien but then has to sue you. If he doesn't sue the lien expires. If he sues he won't win in court because he had a contact with you and now he wants to breach the contract.
There is no reason to pay him for work he is not going to do and it will cost you much more to have someone come in and do the rest of the work since they are not doing the project.
In fact if he walks off the job and you have to pay someone else to do the rest of the work and it costs more than you would have paid him you can sue him for the difference.
You are signing a full release and most assuredly cannot do that.
You are saying you will not sue him no matter what happens. So he is going to walk away and be free. There is no warranty any more and in fact you cannot sue if there is something wrong.
He is bullying you and you should not sign and you should not be afraid of his empty threats. He is not entitled to any more than what your contract states.
In fact in Ontario even if there is just a written quote and not a contract he cannot go more than 10% above the quote or the consumer protection branch will step in .
Does that answer your question?
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