Why? You only need the master craftsman for the electrical inspection. You can theoretically do the rest yourself if you know how. We also did the electrical work up to the meter/distribution box ourselves during the renovation. It's absolutely no rocket science. I just didn't dare to touch the distribution, after all, I'm just an amateur....
Size 77 sqm / as a gallery house Costs about 150k High-quality equipment, machines bought and sold again. I will only be retired in 17 years. All trades worked hard, 36 years of experience. Construction time 12 months including garden
I was just thinking whether you might want to approach the various "house building, living, and do-it-yourself" magazines with your house construction ... they would certainly consider it worth an article. Of course, only if everything is as legally required, otherwise you might encounter problems with the various authorities after a publication.
Do you not have to add the earnings that you miss out on during the year to the costs? Nevertheless, great work! If you do it as a hobby/passion, the costs are also secondary.