Were you overly cautious or did you even have to provide additional funding?

Better leave it, because you were satisfied with the draft, weren't you? Just because suddenly a few thousand (and that at the beginning) more are there, I wouldn't spend that immediately.

Unless you planned a smaller house out of necessity....

We planned the house with a 5% buffer - which is almost gone; sliding door here, shower enclosure there, more drilling meters over there
However, we also planned landscaping, carport, etc. - if push comes to shove, they would be sacrificed.

After purchasing a used house and once everything was finalized, we still had some money left over. Mainly due to equity increasing faster than expected. We then used it immediately for a special repayment in the first few months and then again at the start of the next calendar year.

Hi,
I created an Excel sheet where I entered all the expected costs, including [Außenanlagen], paving, kitchen, etc.

Then I compared all expenses against that and thus always had a pretty good overview.

Our 5% reserve wasn't enough either, but I still didn't have to refinance. Just the 'rest' of the monthly salary went into it...

Cheers, torsan

We withhold a portion of the equity (approx. 50k) and keep it as a "buffer" that hopefully will not be needed. This 50k will then be paid into the special repayment within the first 2 years.

In my opinion, this is a question for the planner and therefore I believe that especially the references can provide very good guidance. Individual answers here hopefully do not influence you, as they most likely have nothing to do with your project.

Where do you want to build?