There is just, really no easy answer for this. Every market is variable. Learning how to read comparable properties and what those differences are, is somewhat of an art. But is crucial to success. An extra bedroom, bathroom, upgraded kitchen or whatever you may discuss, affects the value in different ways depending on where the property is and what it already has. If you have a four bedroom SFR, adding an additional conforming bedroom will probably have a very limited value in Denver. The same addition in Salt Lake City or Boise might make far more sense where larger families are more common. But if you have a 2/1 in Denver, adding a bedroom and bathroom can add huge value. But only if the total square footage allows for that change to still make for rational, comfortable living. And only if the neighborhood supports having that. If the house is in an area where few families live, then even the additional bedroom may cost most than it adds in value.