We rent the entire house, not room rooms.  The nightly rate is indepenedent of the number of guests, with the exception of a $15 extra-guest fee charged for each guest beyond 4.  This fee is intended to offset the additional laundering requirements and water usage of larger groups.
Our rates occasionally vary from day to day.  As of this writing, our standard base rate is $300 per night, which is just $60 per night, per bedroom.  We have a peak rate of $400, which we apply on weekends, major holidays, during Twilight events and during Halloweentown festivities.  Under certain circumstances our rates may be slightly higer.  Peak rates are simply intended to push those with flexible travel plans to less in-demand days to help keep those high-demand days open for those who are restricted to them.
AirBnB makes us roll the 10% Saint Helens vacation rental tax into our nightly rate, so rates will appear 10% higher than stated above on their platform.
We also have last-minute booking discounts enabled on AirBnB. You can snag a 10% discount by booking a trip less than 2-weeks out, or 20% discount by booking a trip less than a week out.