Problem with builder

[slithytove]

Lots of issues but I'll try to keep it short.

New kitchen installed due to finish 21 November.

Wasn't. Still needed snagging (damaged door, missing handle, hole in outside wall), painting, and splashback installing.

Many, many emails got most of this done. He became difficult to get hold of. Hole has not been fixed. Splashbacks were done today.

I wasn't there for the splashback installation. They are vile. Dark grey in a cream and brown kitchen. I emailed to complain and mentioned my other issues too.

He called, and said the job is complete and high standard. He said the hole in the wall is my issue to fix at my cost, as it is because of a waste disposal installation which was not on the original quote. It was however on the final quote.

He says the splashbacks are what we ordered. We ordered frosted. Sadly this was done verbally.

He while on the phone threatened to come round my house to discuss it.

I have still to pay over £1k and he wants it within 7 days. I said he could have until end of jan to make good the issues (replace splashback and repair hole) or I would get someone else to do it and deduct the cost from what I owe him.

Can I do this?
Can he take me to court?
What should I do? I've got 2 kids under 2 and am on maternity leave so at home a lot, this has scared and upset me.

I'm going to ask trading standards as well, but any advice would be so appreciated. Thanks in advance.