Whether they would get back everything they invested over the decades in a sale, no one knows LG
That is the crux of the matter. Only if the property value increases do you usually make a profit. Most owners end up losing money at the end of their life. If your parents had rented all their lives and invested the difference in the stock market, they would surely have much more now than if they sold the 35-year-old detached house. That is the consideration of pure returns and has nothing to do with quality of life. The quality of life was certainly much higher during those 35 years! Conclusion: Do not build/buy a house for the return, but for the quality of life. Owner-occupied property ALWAYS costs a lot of money and ALWAYS decreases in value. That is the truth!