Use garage as house/bungalow?

Hi landlords! I want to ask you a really stupid question. First about me: I am freshly 18 and have extreme everyday stress and also severe family problems. Unfortunately, my financial future looks very bad too. The main issue is basically: I can't take it anymore, I just want to get away from everything, have my peace, be alone and switch off, otherwise I'll die from my stress. That's why I thought, how about my own house? Well, of course I don't have the money for that. But I could raise 15,000 with a lot of work. Then I had an idea: a standard ready-made garage costs on average 3,000€. So why not just build a cheap double garage, save the expensive gate, and just live in it like in a bungalow? Only ground floor, about 30 sqm of living space. Do you think it is possible to simply build a larger ready-made garage on an inexpensive plot, insulate it, install electricity, gas, water connections, and live in it? Without furnishings, just for the construction, 10,000 should be enough. That would basically be a small condominium packaged as a little house. Is that legally feasible and does my calculation add up? Please no lectures about other suggestions, I'm really fed up, I have to get away from everything. I could raise 15k, a small foreclosed plot for 5,000 is easy to find. What do you think?

How about starting with a one- or two-room rental apartment?

Rent is wasted money and I would earn the 15k myself and if it works out, pay everything off in one go, so that I only have to pay taxes, house maintenance, etc. and figure out how to make ends meet.

I won't say anything about your idea now, but for you a Wohnmobil should be the right choice. It doesn't even have to be drivable, you just park it as a permanent camper at the campsite.

what about a wooden bungalow in that size range? it's fully insulated and can be lived in year-round

I agree with Perlenmann, a caravan or something similar on a permanent campsite is available for under 4,000 euros. In addition, there are the site rent and ancillary costs, which are reasonable. Whether one is allowed to live on the campsite year-round must be clarified with the municipality. Since the sites are often in the middle of nowhere, a car is of course advisable.