If you had built your own house, you certainly would not have left these gaps. The bad craftsman just didn't care.
The question is whether you realize that you are making a mistake. The expert came through the front door and saw it immediately even though he was not actually there to inspect the shell construction. At that time, I also thought like Silke. I had noticed that the masons worked slightly outside the tolerance, but that such mistakes could be made...
Topic trailer hitch:
It cost me 600€ from the factory. Cars without a trailer hitch are possible but impractical. And I'm not just saying this because, as a sailor, I tow my boat from the winter storage to the berth twice a year (there used to be more regattas ;)). You can also use it for many other things, and trailers can always be rented cheaply, especially without mileage limits. Also, you can put bike racks on it. Next time, I would tend to choose a fixed trailer hitch, kneeling behind the car is annoying and 50 kilos of tongue weight are very tight for heavy trailers.