Discrepancies with the architect due to construction costs and invoice

Good day everyone,
my wife and I are planning the conversion of a barn that was formerly used for agricultural purposes into living space. The barn dates back to around the 1920s. The operation has been deregistered for an estimated 20 years, which is why the building is only rented out as a parking space for motorhomes, etc. After the operation was deregistered, the entire area was equipped with a reinforced concrete slab, sandblasted from the outside, and repointed, and since it has never become damp inside, according to the structural engineer who inspected the building, the roof truss is in very good condition.

In mid-2017, I started the first planning work myself. I recorded both heights and all measurements, contacted the building authority, created a complete draft, and then submitted a preliminary building inquiry. Around November 2017, I received the green light from the district, so in December I started looking for an architect necessary for service phase 4. Since I am a draftsman by profession, I immediately gave him my finished draft (2D ground floor, upper floor including all existing plans) at the first contact, so that he could get an idea of the project.
I was made aware of an architect by acquaintances and relatives who even lives only 1.5 km away from the project and is said to do good work.
After the first talks, he started working and in April gave me the first promise that he would have the documents ready the following week and they could be forwarded to the building authority. Apart from minor details such as shifting windows, he adopted my draft almost entirely in 3D and extended the drawings with views and sections.
Until December 2018, there were countless excuses, apologies after I complained, promises that the documents would be compiled next week, periods during which he did not get in touch at all, until he finally actually had finished the documents and asked us for a final appointment. Until this appointment, he unfortunately was unable or unwilling to provide me, despite repeated inquiries, with the estimated construction costs so that one could adapt the concept again with one’s own cost assumptions (I believe this is part of service phase 3?!).

At the appointment, he then unfolded his finished plan, described the project again, and subsequently presented his estimated construction costs. However, before we got to the construction costs and he explained everything to us again, I already noticed that he had not adhered to some agreements that mainly concerned the construction costs. For example, he calculated with a Poroton-S9 instead of air, insulation, and a KS block. He added the conversion of an attic, which is above the already existing garage in the building and which, after clear agreement, if at all, will only be converted in 25/30 years, as well as the garage itself. He added that his estimate is based on everything being commissioned and nothing being done in self-performance. Of course, that is completely made up. The agreement was that only the shell and necessary roof work would be contracted if anything.

From his calculation, I then saw that he applied an honorarium rate of about 10.84% of the calculated nearly 465,000 (without considering the above agreements), which would result in about 51,000 for him for all service phases. In addition to the 3% from service phase 4, he charged 12% from service phase 3, which in my opinion absolutely does not add up. I assumed that since he still had to incorporate/trace my draft and made minor changes, he would apply about 5-7%, but 12% is 80% of the maximum applicable 15%, and he definitely did not perform this work in service phase 3. Overall, he now comes up with additional incidental costs for printing, “site plan,” etc., amounting to over 10,000.
Of course, I disputed his invoice before Christmas. My question now is, do I have the right to a new cost estimate and architect’s invoice, and do architects usually calculate construction costs by m², m³, or something similar so that their own invoice turns out as high as possible?

Many thanks and kind regards, A.H.

Is there anything in writing from the "initial talks" in which the commissioning took place, such as emails or meeting minutes? The delay of eight months alone could be a case for damages, e.g., increased material and labor costs in the meantime. In any case, he eventually delivered, and you have to pay for that. Was it really only about the shell construction project with shell construction costs of xy€ or was the planning up to move-in ready discussed and commissioned as well? I mean, whether own work is included or not, the project volume is what it is, only that own work is equity, but in the end, there is a house for 465K€ there, and the architect’s fee is based on that.

What amount do you have in mind? Who will handle the communication after the application? I would be careful about falling out with the architect.

I mean, whether own contribution is included or not, the project volume is what it is, only that own contribution is equity, but in the end there is a house for 465K€ and the architect's fee is based on that.

The statement is completely correct. Own contributions (unfortunately) do not play a role here.

Do you have a written preliminary contract? Often architects work in advance. Usually, however, there would then be a cost estimate for service phase 2 and not only service phase 3 or 4. It is very unusual for him to base the costs only on the submission planning. Normally, this is where the refinement of the first cost estimate takes place, on which the fee is based.

The problem now is that you have already commissioned the service, even if only verbally, by handing him plans with the request to create the submission planning. You should only do this once you have the first cost estimate. Even if there is nothing in writing, the verbal order counts in this case.

So you will have to pay for the service rendered so far. That your plan was largely ready beforehand is irrelevant if no explicit agreement was made beforehand.

We also handed our architect a finished floor plan, which he had little to improve. Nevertheless, you pay the fee established for the phase for creating the official documents and drawings.

And even if the architect were to charge below the fee here, one has to be careful, because then a claim for the fee could be made afterwards.

Regards