Our construction cost overview - It can also be "affordable"

Then go to the basement. p

And of course I only find out about something like this after the fun is already over.

We previously lived in an uninsulated half-timbered house with single glazing. We then had an indoor temperature of 32 degrees and survived. So with triple glazing and an insulated roof it should be somewhat better. And if necessary, there are curtains or blinds. In our first apartment we never used the roller shutters and always had a very pleasant temperature. After all, we still live in Germany. For 10 hot days a year when it could become unbearable inside, I won’t have ugly roller shutters installed and then have switches for them in every room.

Not quite. Everyone as they can.
We have almost the same infrastructure as the OP, paying about ±150€/sqm. This is the Hamburg commuter belt.
But I also grew up here and have my permanent job here. My profession is a rarity, so hardly any opportunities to look elsewhere.
When I was still commuting to Hamburg (30 km), there were some colleagues who moved 89 km away to an area with cheaper building land.
The result was that at every snowflake or storm/rain at night, people liked to call in sick because it was inconvenient to shovel their way out of the snow in the middle of nowhere.

Good infrastructure is priceless: rural means for families that mom plays taxi for the kids, in old age rural can mean loneliness and dependency.

For us, a higher loan for the 150€/sqm for a plot that must be at least 650sqm would be manageable, but it feels like "I don’t want to". We decided on leasehold... somehow it comes to the same thing anyway, but there wouldn’t have been any other plots in our area either.

We built in a village of 2,000 souls, were received fantastically, have a kindergarten and a school within a 3-minute walk, a pharmacy, a doctor, two bakeries (with mini supermarket) and twice a week a sausage and cheese truck... and at least VDSL.

It’s 6 km to my old hometown, i.e. 2 minutes by car, where all the stores etc. are.

We probably won’t die lonely (the cemetery is next door though, saves good transport costs), but our child will later have to use bus, bike & car. That’s how it is, nobody dies from it... almost everyone drives to shop anyway.

For that we don’t have a garden where everyone peeks in, didn’t pay 300 €/sqm (6km away it’s like that if you can get anything), we have a river and looooooads of forests/meadows around us.

We have both lived for years in cities like Berlin & Münster, as well as in normal towns, but then centrally – never again.