But it won't be to whomever inherits the house.
Well for that to matter we'd have to assume that Markus bought the club in order for his already rich daughter to some day profit from it. (I mean, he obviously did intend for that to happen, but I don't think he wanted to buy a football club for that reason.)
And I'm still far from convinced that the investments he's made in the club could have increased its value by an amount greater than the total amount he's invested. Investments in capital surely increase the club's value by the same amount as the money invested, and all that can really change the value of capital over time is depreciation, which decreases its value. Expenditure on transfer fees can return a profit when the player is sold on, but the money you spend on salaries and agent fees cannot be earned back. We've earned money from promotion and TV rights but that's reinvested into the budgets for the aforementioned things. I think Randy Lerner has claimed it would be an idiotic decision to buy a football club with the intention of making money, and I can see where he's coming from.
Katharina can make a nice bundle now, because it wasn't her money to begin with. The club could have been relegated to the Conference and been worth less £1m at this point but that'd still be £1m gained to her if she sold it.