The difference would be that if you sell your house for 100k now, you'll have 25k extra after "moving up" to the 75k (previously 150k) house, minus a few years

The difference would be that if you sell your house for 100k now, you'll have 25k extra after "moving up" to the 75k (previously 150k) house, minus a few years of rent that you might have paid in the meantime. This is assuming that you put your profit into something that doesn't lose 50% of its value like your house will. The stock market might crash just as badly, or your property value might rise even higher and sitting on (otherwise secure) cash equivalents will lower your real wealth. So we don't really know, right? I think the only takeaway here is to invest large sums into a single asset class (real estate, or stocks, or cash) if you're playing to win, or diversify among dissimilar asset classes (with your house only being one of several types of investments) if you're playing not to lose.