Kitchen seller wants the remaining payment in cash, does not want a transfer

Isn't that also somewhat one-sided? Objectively speaking: If he had taken the handle into account, you would have had to pay for the aperture/strip as well, right? So why argue about it? Furthermore, your indecision and your wife's subsequent changes probably caused the overtime. Surely he could have pointed out to you that if you don't make a final decision and he continues building and then everything has to be shifted afterwards, the corresponding overtime hours have to be paid. By the way, I also see it that you can't withhold the entire payment for defects, but only an appropriate amount. If several people do that, it's no wonder that accounts get seized. Just a thought.

If he had considered the handle, you would have had to pay for the front/panel as well, right? So why argue about it?

No, he could have moved the kitchen from the very beginning if he had noticed it during assembly.

If he hadn't changed it, we would have needed a different handle for the patio door, and who would have had to pay for that?

I don't want to withhold all the money either, but he has to fix the silicone work; he will get every cent from me.

His account was seized because he took several deposits and didn't deliver any kitchens.

The kitchen accounted for about 4% of my total costs...

Regarding money, the kitchen builder/kitchen salesperson was the only one who caused problems.

All other trades received their payments on time.

I don’t understand at all why you have to justify yourself here like this. And how you can still remain so patient.
By being cautious, you’re not only protecting yourself but possibly also creditors. So other customers, suppliers, etc.
If there is such a justified suspicion, I would follow the advice given further up and also contact consumer protection and/or the chamber of crafts to ask how you should proceed.

I don’t understand at all why you have to justify yourself here so much. And still remain so patient. You are protecting not only yourself through your caution, but possibly also creditors. So other customers, suppliers, etc. If such a well-founded suspicion exists, I would also follow the recommendation mentioned above to contact consumer protection and/or the Chamber of Crafts and ask how you should proceed.

I’m on it ...... the Chamber of Crafts can only say: "The company is still current"

The consumer advice center is not reachable until tomorrow.

I don't understand at all why you feel the need to justify yourself here. And still remain so patient. You are not only protecting yourself through your caution, but possibly also creditors. So other customers, suppliers, etc. If there is a justified suspicion, I would recommend, as mentioned above, to also contact consumer protection and/or the Chamber of Crafts and ask how you should proceed.

So it is only about "revenge". NO ONE is protected by this; the original poster is simply acting in breach of contract if he transfers the payment. From a human point of view, each individual point may even be understandable. Legally, however, the original poster must comply with the contract. For the remedy of defects, of course, a reasonable amount can be withheld. The rest must be paid. And in cash. Provided that no entry regarding insolvency or impending insolvency is visible in the public announcements.