Legal Question in Business Law in New Zealand (Aotearoa)

Re: contractual obligations

A party to a contract who says that they won't perform unless you pay them more than the contract price and release them from liability, etc. is in "anticipatory breach" of contract. Their demands are improper and they are, from what you describe, trying to hold you up unfairly. If you are dealing with a licensed general contractor, you can complain to the Registrar of Contractors, but that does not get the work done at the contract price.

You are in a bad situation as a practical matter. It is hard to imagine that you will get the work done properly whether you pay more or not, because how can you trust someone who acts in this manner. When someone tries to "get more" and fails, I would not want them to do any more work.

It seems to me that you need to get another contractor who is honest and trustworthy, and take action against the contractor you have now for breach of contract and damages, the difference between what the current contract provides and what it costs you to have someone else do the work.

If you sign a contract which makes the changes demanded by your contractor, it will be difficult later to make a complaint and most likely you will be bound.

Re: contractual obligations

It's not clear if you are employing people or whether they are on self-employed contracts.

Either way, you cannot be forced to change the contract and you are not required to accept new conditions that they try to insert. You may choose to accept new conditions if you fear to lose their work.

If you sign a new contract you are bound by it. However, if you refuse to agree they are bound by the old contract until they notify you that they will not do work any more. There may be termination clauses in the agreement, and if so they are legally bound to keep to those and give you the specified notice to quit.