Don't let the people here in the forum tell you that it can't be done. And those 3000 euros per square meter only apply if you don't want to lift a finger yourself.
Two years ago, I started building a city villa in timber frame construction. Without a basement, on a slab. I did everything myself. The only craftsmen were a master carpenter for setting it up—for 4 hours—a civil engineering company for concreting the slab, and the window installers. You have much better conditions than I did. So do it. My villa is now completely finished from the outside and has 192 square meters of living space, and I still have about 1.5 years of interior finishing ahead of me. So far, the whole thing has cost me 148,000 euros. If I put another 100,000 into the interior finishing, I'll be at a cost of about 1300 euros per square meter. But then it will also be a palace. Including a 45-meter-long driveway. I just pay with 3.5 years of my life. Get started—it’s the best thing I've done in my life so far!
Plan created yourself?
Statics calculated yourself?
Measured yourself?
Soil survey done yourself?
Excavated the building pit yourself?
Removed the excavation yourself?
All foundation work except the 4 hours of the civil engineering company done yourself? (Installed frost skirts/strip foundation/padding)
Designed the house yourself?
House erected with really only one additional carpenter?
I’m curious how you’ll manage the stucco, electrical, painting, and sanitary work all by yourself.
I have been on construction sites many times; my father, brother, and grandfather were/are professionals. None of them built a house by themselves together with one other person. But I always enjoy these stories.