Affordable homeownership - Is a house with land still realistic?

By the way, I built my house for under 2,000 EUR/m², turnkey with a lot, a lot of own work. And those are already the prices after the Corona price shock 2022...

I also did a full renovation to almost KfW standard for well under 1,000€/m², even in EL. So? Does it help anyone to bash EL when the OP wants to build turnkey? We are comparing normal and market-standard prices here. With EL, the world always looks different.

Nope, that is indeed an absolutely reasonable calculation. 50k is not much,

... if you consider that this is the bare "from" price and everything else is missing. You just have to be able to pay it.

I am currently working on a project that aims to make affordable housing more realistic again – that is, compact, modern houses at a fair price.

Please not the ninety-eighth rehash of such brilliant innovations ;-) like modular and/or tiny houses!

People "don’t" even want single-family houses anymore – multi-family houses are much more efficient...

Multi-family houses are castles in the air, where the market only provides single plots of land that then, just because of the purchase price, cannot be built with a detached single-family house but have to be divided for a duplex. In theory and practice, it has always been clear which of the two wins.

I am currently working on a project that aims to make affordable housing more realistic again – that is, compact, modern houses at a fair price.

That has existed since the 1950s and was called prefab houses. Quattrohaus, terraced house, townhouse, etc. And other companies have repeatedly rethought and expanded on that depending on their corporate philosophy. So nothing is new about this project.

What is most important to you in a home? (e.g. plot size, garden, room layout, etc.)

I can only understand the question as far as what I can influence as a builder. Plot size, municipal politics, or broader aspects I don't see as levers, except that as a builder I have to or can question my own needs. Everyone is different, and many can afford a home in the size they want. That depends on salaries, which cannot be influenced by the planner either.

Would a smaller living area (70–100 m²) or a smaller plot also be interesting to you if price and quality are right?

To be honest, the questions are too general and sweeping for me. Besides, there are enough houses that, when you subtract the necessary hallways and technical rooms, cover those 70-100 sqm. And enough houses with appropriate living space size also quickly leave the market because they are bought when you watch the market or look around in your own area. There is no need to reinvent the wheel. It already exists.