Is a 180 sqm house feasible for 300,000 EUR?

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Possibly houses of this size with 6 rooms?
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Would it also be an option for you, just as an idea, to look for two small semi-detached houses from the providers of smaller houses? You will need several bathrooms anyway. If the development plan for your future property allows it, you could possibly create a passage in the middle of the houses, which you can close again when you no longer need as many rooms and sell one of the two houses. Maybe as a teacher and self-employed person you can deduct an entire semi-detached house from your taxes? Small semi-detached houses are, as far as I know, not much more expensive than a single large house and the providers that you had to exclude so far because they do not build such large houses might then also be options for you. Additionally, you can spread out the self-performed work over time a bit.

If I use current free loan calculators - so without touching the score, then with 2,000 EUR monthly it's about 33 years.

We are both 40, the oldest is 12. Yes, he could be out of the house in 8 years, or maybe not. Berlin is not far anyway.

Please also keep in mind when calculating that very few financiers will lend you money up to the statutory retirement age, thanks to Basel II. And civil servants in B or BB will hardly have to work until 73 - right?

So you will be able to finance for a maximum of 25 or 27 years, of course less with a later start of construction.

I don’t know if you still need a house near Greater Berlin with children who are 12 years old

Why not? The oldest child is 12, probably will still live in the house for 6 or more years. The other children even longer.

What are you assuming? I simply don’t understand your objection.

Why not? The oldest child is 12, probably will still live in the house for 6 or more years. The other children even longer.

The original poster doesn’t even have a plot of land or financing. So it will probably take about two more years, or rather longer, until he turns his house key for the first time...

Ok. If there is no property yet and no financing, my thoughts are unnecessary.