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I'm a big fan of combining residential with sporting facilities.
You are effectively paying for a 24/7 box.
The maximum width of a ground is 70m, so allowing for 15m either side on a bit of angle, if you could get two floors of grandstand and then units with balconies 10m wide (+ the 15 in either corner), say five floors. You are looking at 5 x 9 = 45 units with (? $500k - $1m ? Depends on what is out the other window I guess) views. Add in perhaps another floor behind the stand with ten permanent seats in the stand. Ground floor becomes your offices and shop etc (and access for units). That adds up to some serious coin for the development.