How do you figure out what values to use when scaling a room?

This is my first time using Unreal Engine 4. I am working on the first level of a game. I have walls placed in the world and lined up together. They are all CubeMesh actors. What i’m not sure on is the XYZ values that can be changed in reference to the scale. Do these numbers match up with feet or inches or any unit of measurement? I tried them as feet and the scale still seems to large compared to the player actor. Any tips?