Estimate cost f adding a corner closet
Lumber 10 2x4x8 at 2.15 = $21.15
Sheet rock 3 pieces $35.00
6 panel door 100-125
sheet rock mud $25
For under $500 you may add a closet do it yourself and cute that in half a good sales associate at Home Depot can walk you through how to do it
You are asking a very good question! First I will say that the answer depends on where the home is located. If the home is located the the greater Albuquerque area, the room must have a closet to define it as a bedroom according the the local MLS regulations.
The room must also have a window to create a safe exit in case of a fire.
I hope this answers your question, if you are looking for a home now, it is a great time to buy! Happy house hunting!
Of course for an older home I think its a case by case basis IMO.