Is house construction financing possible? - Fully paid-off house

Here is the property from above. Parking space in the front and terrace with some lawn at the back. I think we are only allowed to build two-story.

Since the financial framework for a new building is now roughly outlined, you could just keep your eyes open. Are there even any plots of land that would be suitable for you and what do they actually cost?
Buying from a developer is an expensive option in terms of additional costs – since the property transfer tax applies to the total amount. Hopefully, at least no broker is involved. And this money is simply gone. Without any tangible value in return.
If you like living where you are now – why change? I would then also recommend checking with an expert how the existing house can be adapted. Suggestions have already been made here.
I have to pay off the place until retirement and possibly beyond, and I would give a lot to be able to be debt-free at a young age so relaxed.

Here are some pictures

That looks thoughtfully done. Whoever likes it will not want to give it up. Staying in seems like a good option. Outsource [Homeoffice] if another child comes and everything fits.

Can't you build something on top of the garage? That could be enough for a HO...

How about an insulated garden house attached to the garage - initially declared as a garden house and then converted into a home office? For heating, a heated mat under the feet and an infrared heater, for example?