Planning a multi-family house - optimizing costs

Sure. But if she spends the money and ends up in care, of course I am already financially (and morally) responsible. And I do see that risk.

From €100,000 gross. You alone, not household income. I think you'll be far from that. Is it morally okay to incapacitate the mother now so that she is not allowed to realize her dream home?

Additionally, it is clear to me that I won’t "leave her hanging" (apart from financing the matter). I’m just trying to put this completely crooked construct she has insisted on so far on somewhat sensible footing. But I certainly won’t ruin myself doing so. That would be the limit where I’d have to draw the line.

No, sometimes you really have to draw a clear line early on and not stubbornly push through every nonsense. Clear words and firmly putting the brakes on the plan so that you don’t go along with it. That helps your mother more than building castles in the air and giving her the impression that it might somehow work.

Sure. But if she spends the money and ends up in care, of course I am already financially (and morally) responsible. And I do see that risk.

Probably not financially. A) you would have to earn really really well and b) she has enough assets anyway. Morally, I fully agree with you.

She would then simply build on her own, with the mentioned consequences,

But the consequences are only in the subjunctive. Possible consequences (financially), not definite ones!

From €100,000 gross. You alone, not family income. I think you will be far from that.
Is it morally okay to put the mother under guardianship already so she is not allowed to realize her dream home?

Normal gross, or taxable gross?
Morally, putting someone under guardianship is not okay for me, not even remotely as a thought.

No, sometimes you have to draw a clear line very early and not pursue every nonsense at all costs. Clear words and clearly putting a stop to the plan so that you don’t go along with it. That helps your mother more than building castles in the air and giving her the impression that it will somehow work out.

I agree with you, but I’m not the only one involved... And if the others eventually also give up and support the idea so that she feels emotionally better, then I stand alone and am the bad son who only wants to enrich himself in the end... (It’s not said that clearly, but that’s the insinuation.)

I had originally drawn the line too, wanted to completely stay out of it, and then the plot was bought on the spot without looking at the plan beforehand (and a few other "exciting things").

I only got involved again when a prefab house salesman advised her to transfer the plot to me, that I should build with a big loan (from his broker) because then I would get a lot of depreciation ;-), she moves in, then pays me rent (which is then factored into the tax burden).

That’s when I was brought back on board to hear the “great” idea... Since then I’ve been trying to correct a lot of nonsense. She would ruin herself in good faith if she continued alone, or with further support.

Honestly, it’s also getting to me. She only wants the best in a positive sense, but she is so trapped in her wishes that she completely stands in her own way.

Now we’ve kind of ended up more in the psychology forum ;-)

Financially probably not. A) you would have to earn really, really well and b) she has sufficient assets. Morally I am fully with you.

The consequences are only in the subjunctive mood. Possible consequences (financial), not fixed!

The consequences, given the statistical life expectancy (and in our family we tend to have significant longevity), the previous bungalow costs, and what she would have to "consume" monthly from the capital, are likely in 10 - 15 years. If she invests it in stocks and there is a downturn, even probably sooner. And then selling her own bungalow and moving somewhere else, I fear she would not survive that.

That is my dilemma.

My mother originally wanted to build a bungalow for herself on the property. The problem was that the price per m2 became so high that all her savings would have been gone, and in case of needing care or longevity she would have had to sell the bungalow. We want to spare her that trauma in old age.

I have not yet understood what would make a 120 sqm living space bungalow so expensive per sqm that it would only be due to the building shape. After all, we are talking about a property apparently intended for one to two residential units.

Since my wife and I wanted to buy 1-2 small condominiums for retirement provision in the next few years, the plan came about that we join forces,

I consider asset investments serving retirement provision extremely dangerous to undertake together with people who, to put it mildly, have "a completely different investment behavior." Boats where rowing in different directions is attempted tend to capsize. Imagine a fund managed by Tom in even weeks and by Jerry in odd weeks — how do you think it will perform?
As your wife, I would already bookmark the page with divorce lawyers in the Yellow Pages if you were to jeopardize our joint retirement provision by concluding from the capitulation in trying to wake up my diva-like mother-in-law that we would have to get into turbulence together with her.
Am I correct in assuming that you madam have not yet been blessed with grandchildren (, whose future would also suffer)?
I would probably play through house models here that, based on a bungalow, utilize the second full floor permitted here for a full-fledged rental residential unit. I would avoid putting mother with a saw and wife on the same branch. Nitro and glycerin belong in separate bottles, otherwise boom!!!

Difficult situation with the mother. Sometimes it is hard for children to take advice (without judgment). For us, an objective "moderator" helped. A good family friend of the same age as the parents, highly respected by them for his life's work. We all sat down at the table and went through ALL possible scenarios together and, above all, calculated them. In doing so, one and especially the other actually had a revelation, and from an outsider, a few tips could suddenly be accepted, for which the children had already received heated ears several times. This was the best solution for everyone.