Beginners: Financing a single-family house with land

At my employer (credit institution), in such cases with fluctuating one-time payments/commissions, an average of the last three years is used as a basis for financing. Of course, it would be more elegant if the financing were not directly dependent on this. Since the payments have only recently been agreed upon, there are no experience values available yet. Only your bank can tell you how they handle this. 10 banks, 10 different answers.

Personally, I would advise you to first buy the property with equity (when the first special payment is in the account) and then wait another two years to see how the payments actually turn out. A range between 35k and 50k p.a. is not an insignificant span.
If you have the property, plus verifiable commissions, that is sufficient as collateral.
At the moment, the equity is still too low for such a volume.

Is this acceptable or feasible for banks?

in black and white, the contract reviewers only have the last 3 months as salary statements on file.

you should definitely schedule a bank appointment!

The 35,000 € are certain

Is this okay or feasible for banks?

Are the first 35,000 € also fixed in the contract without performance or sales targets here? Are they unconditional? If yes, banks should have little problem crediting that, otherwise you first have to find the right bank. A case for the typical loan brokers; they will know which bank will cooperate.

I think it will not be difficult at all to be offered 600k with a fixed salary of 4800€.

As far as I read it, you don’t have a plot of land in sight yet, do you? I would first cash out the 50k annually for 3 years and additionally save as much as possible from the monthly income, then the starting situation would be completely different!

The question is how the Corona crisis affects the construction industry and real estate prices. Maybe in a year there will already be a suitable plot for 300€ per m² and at the same time you will have significantly more saved up. But it is also a certain risk if things don’t develop that way.