My question is whether there is any argument in favor of special repayment (5% p.a. possible)? I can't really think of anything. I would therefore put the money into the portfolio.
Your solution would also be mine - without me being a professional.
With 3.4% interest I would definitely make special repayments and not gamble with the money on the stock market. Stock prices are heavily overvalued and a major stock market crash is imminent.
That is a solid point of view which I do not share. Of course, you can gamble on the stock market, but you can also invest (or have it invested) properly – or both.
Why does one actually do something like that?
I ask myself the question "why do you do that," too, because I had bad experiences as a landlord. A kind of tenant nomad got us into trouble. I thought – either you have 10 apartments and the 9 suffice to partly finance a tenth, or you sell the apartment. I couldn’t finance ten, so I sold the one.
Because I just calculated that you only get your money back after 27 years.
Consider exactly who uses which money and you realize that the tenant buys the apartment from the landlord.