How to price the master bedroom fairly
List the benefits: more square footage, private bath, closet, balcony, parking, light, quiet, or direct access. List drawbacks too, such as street noise or serving as the path to a shared space. Compare those features with the other rooms.
Start from an equal split and add a modest premium for durable advantages. Use a blind bid if the household cannot agree. The total rent must still match the lease; do not invent a premium without explaining it.
Write the result down before anyone commits to the room.