The annoying topic - Is the construction project affordable?

Contrary to emer's opinion, I must say that we neither reckon with nor ignore nonexistent income, let alone want to exclude certain feedback. To be honest, I also don't know how one comes up with this almost reproachful train of thought.

[...]

I know that in my industry and especially companies, significantly more income is possible, and my girlfriend, through civil service status at about 50 years old, also earns around 3,000 euros net.

Yeah, how could I even come up with such an idea. ;)

And where do you now see that priced into the calculation of the first post? The fact that one has more income in the public sector regardless of performance simply through "aging" is a fact. Of course, that is reassuring and accordingly more "plannable," but it is not taken into account in the calculation. The first post states that we are currently saving 2,000 euros every month via standing order. Additionally, the current cold rent of 550 euros would no longer apply. Added to this is a budgeted buffer of 800 euros for "pocket money" as well as – if money were really tight – two Riester contracts worth ~250 euros that can be set to contribution-free.

I also don't see any mistake in it now. On the contrary: it is important and wise to also develop future scenarios.

A note after the many good tips:

You say that you want to spend 40 TEUR on kitchen/furniture. This amount must be considered outside the construction financing because it would be an interest cost driver. Then you quickly end up with a 110% or 120% financing.

20% equity would be very conservative as a statement. However, if furniture is included in that, then it is certainly a good reference point. After deducting the furniture, you cover incidental costs and some other extras with the remainder.

And where do you see that priced in the calculation of the first post?
The fact that in the public sector you get more income performance-independently just by "aging" is a fact.
Of course, this is reassuring and accordingly also "more predictable," but it is not considered in the calculation.
In the first post it says that we currently save 2,000 euros every month by standing order. Additionally, the current cold rent of 550 euros would no longer apply. Added to this is a calculated buffer of 800 euros for "pocket money" as well as - if there were really a shortage - two Riester contracts amounting to ~250 euros, which can be set contribution-free.

I don't need a justification from you. I'm only looking at it critically. :)

Realistically considered, I just suggest:

You have a rough cost plan, and it is so rough that the ceiling has definitely not been reached.

In doing so, you are already building on at least 3 calculation errors in your initial post.

1. Your ongoing monthly expenses and savings rates exceed your ongoing monthly income in your calculation by over 200€.

2.

* Land - 40,000 EUR (800 m²)
* Additional construction costs - 80,000 EUR (incl. paving and garden landscaping)
* House - 300,000 EUR (ready for finishing)
* Garage + carport - 15,000 EUR

* Total: 405,000 EUR

They add up to 435,000€ and not 405,000€.

With that, you come in your calculation to a total requirement of 476,000€ plus (and you write this yourself) X€

That means, even if you want to finance "only" 450,000€, your entire equity is already used up in your total requirement. There is zero room left.

3. Assume that the whole thing – the further you plan – won’t get cheaper unless your lump sum "house" (in sqm) is not too big and there is no basement underneath.

And please: Don’t count on money you don’t have yet. Contracts or no contracts. What I don’t have today, I can’t spend today either. If later you have more money, be happy about it; but planning "tight" today because the money is "tomorrow" is still not a good plan.

Enjoy the rest.

I don't see any mistake in it now either. On the contrary: it is important and wise to also develop future scenarios.

Yes, the approach of risk analysis is not bad either and seems to be recognized by numerous insurances. However, in this future scenario, the focus is only on the positive risks (opportunities), namely the "definitely improved income situation."

Cherry picking is not the best method for scenario analysis.