Is an offer binding or are deviations allowed?

I don’t understand how anyone can argue like HilfeHilfe.

I feel the same way.

We have an email where he responds last: attached is the offer adjusted as requested without the swallow and with a simple garage.... BUT we don’t have any email from us saying: ok, accepted like this, so presumably no written contract exists.

And then we received a statement = invoice containing completely different things and which is higher than anything we were offered before.

At this point, I have to say, that is pretty naive. You are the client, meaning you are ultimately responsible for proper handling and supervision; you are authorized to issue instructions on the construction site. With sums like these, formalities must be observed. Otherwise, you will quickly have problems with defect claims. Then it’s: Where is the contract? Where is the agreed warranty period stated? What are the payment terms? Etc. etc.!

So, you should at least print out the offer, add handwritten notes if necessary (start and duration of execution, etc.), "I hereby commission ...", sign it, and send back a copy. On the other hand, as a craftsman, I wouldn’t have even started work without a clear order. For the craftsman the situation is actually much more uncomfortable than for you: If he doesn’t have a verifiable order, you can exercise your house rights and throw him off the site, have his work undone at his expense, consider the invoice null and void – to put it bluntly. Besides, the craftsman lacks a proper specification to work from: Which materials, where are the scope and interfaces with other trades, etc. Should he piece all that together from various offers? That WILL cause disputes.

Just because they are fundamentally cheaper doesn’t mean he can’t sell them to you at a higher price; I would be cautious here. It could become an issue that you don’t have a new offer for that; maybe it helps that you requested it, but otherwise he can probably set the price for the bricks himself.

He can’t set it himself: Due to the prescribed “same calculation basis” for change orders arising from modified services. Therefore, his statement that he could charge any price is basically just a sign of his ignorance, or simply a cheeky attempt. Additional costs can only be claimed if he can prove a correspondingly higher purchase price – which is not to be expected, based on the previous descriptions.

Put in a written objection, thereby disputing the invoice. Pay the agreed purchase price, keep back some amount calmly so he cleans up his mess, and a little more because it wasn’t executed as contractually agreed.

Exactly. If you claim a defect due to the missing vapor barrier, you can withhold a few thousand for that as well. Provided he has no further work to do for you, I would also ban him from the property.

Print everything out and go to the lawyer!

What do you expect from us

What do you expect from us

In any case, no irrational recommendations like

off to the lawyer!

... even though that is of course just my opinion

Well, a lawyer also costs a lot of money and nerves, and so far I had tried to settle it amicably with him....

Yes, and sure, that was naive, we should have replied by email that we accept the 3rd offer. But he himself can’t claim that I ordered nothing, otherwise he’d be in trouble himself. You can only argue about what was ordered (so dovetail or not), but I’m not even arguing about that right now, I said I’ll pay for that.

The rest is just outrageous on his part.

I’m going to reflect now and consider: going straight for the heavy artillery:

1) Get a lawyer involved, get an expert involved, then withhold money because of defects --> costs me money and nerves, but if there is a defect after the Blower Door test I have to go this way anyway

2) Pay for what I received and what’s on the roof, hope the roof is alright, I face a lawsuit from him calmly, I have too much in hand and everything in writing, he even writes that he just demands what he wants and that has nothing to do with a calculation, but if there’s a problem with the roof then I have a problem

Laymanly, I would claim that he has to rely on the email in which you write that the offer is accepted with the modification that different bricks are used which are cheaper. Subsequently, he starts the work, which I would personally understand as an implied action and as acceptance of your offer. Thus, the lower price for the bricks is also part of it; otherwise, he would have had to explicitly point out that this is not the case. But that's just my layman's opinion.

I wouldn't do anything with a lawyer and expert. Properly reduce the price because of the defects recognizable to you as a layman. Point out that you are happy to settle it in court with experts, etc., briefly explain to him what you know and that you have already sought legal advice.

If he has any brains, he will say yes and amen, then slink away like a beaten dog and hopefully think about what he is doing with the next customer.

Even if he wants more, let him go to court and pay for the first expert, which raises the threshold for him significantly because it involves costs that he is not sure to recover.

You can put the saved money aside in case the work is faulty and you have repair and maintenance costs earlier than expected.

And first and foremost, it is really important to lodge an objection against the invoice, in writing, by registered mail.

So we are now at the lawyer next week because we received a payment order against the invoice, of course, we had raised a written objection....just a question about the whole thing: with the visible roof truss it is common practice that in some rooms the beams are closer together and in the next room then further apart....at least I have often seen it that way.....that the bedroom, for example, has closer spacing, then the corridor wider spacing for example because of the skylights and then another room further on has a different spacing again...

But is it normal that the change from close to wide takes place in the middle of the entrance/visible area of a room???