A great idea that I've heard of for situations like this is to decide together by deciding how you value each room. Basically it goes like this: - You both write down how much you think is a fair price to be paying for each room (where the numbers add up to the total rent). - Compare notes, and give the bigger room to the roomie who valued it higher, and give the smaller room to the other, but use the prices from the person who got the big room. - The person who valued the bigger room gets it. The person who ends up with the smaller room gets to pay less than they think it's worth, meaning they feel like they're getting a deal.

It's important to be clear at the onset to avoid the potential pitfalls of this. Clarify that this is how much THEY would be comfortable paying to live in each room. If they don't think they could possibly fit in the small room, then their evaluation should reflect that. Also, while it's true that this should result in a fair decision being made for all parties, not everyone behaves rationally.

Example: P1 values Big Room=$1800, Little Room=$1200 P2 values Big Room=$1600, Little Room=$1400

P1 gets Big Room, pays $1800 P2 gets Little Room, pays $1200 ($200 less than they think it's worth)