[HDThoreaun]

> if you double the rent of (nearly) all flats, everybody will still be willing to pay that doubled price.

This just isn't true. Many people would move in together, many others would go somewhere cheaper. That would lead to vacant units and landlords would have to lower prices to fill them.

[thelastgallon]

Like what happens in bay area. Many people would move in together and rents keep getting lower and lower!