Generally you don't. First come, first serve. If you're not willing to pay the area-proportional price of the room, someone else will be.
The only situation where this would be relevant is if you're a group of friends all looking for a new apartment together. After university, that's pretty unusual.
You're saying that if a unit has two 500 square foot bedrooms, and one is in the basement with no windows next to the furnace and the other is upstairs with bay windows on two walls facing a garden, there is always someone willing to pay half of the overall rent for the basement unit? How exactly are you arriving at this extremely counter intuitive conclusion?
As a son of a landlord who rents rooms, I can tell you that people are not willing to rent a room with no windows for the same price as one with a window, even if they have the same area.
If we adopted a single price, it would either force us to lower the price of the other rooms significantly or keep the interior rooms unoccupied.
"If we adopted a single price, it would either force us to lower the price of the other rooms significantly"
If you did that though wouldn't people still feel that it was unfair? (The frame of reference would just be lowered).
I'm also curious if there is a difference between stating something as a discount (to offset inferiority) vs. the same thing where the better room is state as a premium.
My gut says better to price as "premium" for something better than to offer a discount. (This seems to be the way hotels usually do pricing as only one example).
If you did that though wouldn't people still feel that it was unfair?
I wasn't really referring to people's sense of fairness - people just decide that a window is valuable enough that they're willing to pay a premium for it (it's around 20%, in our case).
I can see it generating some resentment, but we've never tried it, so I can't say for sure.
I'm also curious if there is a difference between stating something as a discount vs. the same thing where the better room is state as a premium.
Well, we don't label it as neither of those, but I think that calling a window a "premium" might be difficult, especially when almost all the products in the market (rented rooms) have one or more. The interior rooms are really an exception.
The only situation where this would be relevant is if you're a group of friends all looking for a new apartment together. After university, that's pretty unusual.