I mean.. they did loan the money, with all the associated responsibilities and risks of loaning money. And they did do the work. All the agreements were entered voluntarily, so what's the fault here?
The best option.. for what? To live in? To invest in? To look at? Besides, isn't it incredibly personal? What's the best option for someone, might be a poor option for someone else.
The back of my fridge is more interesting than this comment. Why am I replying to this comment then, rather than looking at the back of my fridge? Hmm...
Then keep on doing what you are doing. You are the one who started this discussion on buying land and building houses. We were talking about Switzerland.