Which ever measurement system you use. It is best to import some of the basic stuff from FPSC, Like a floor and a wall and a character.
Place these in the center of the scene.
English units the full grid is 8'4" x 8'4" x 8'4"
Metric units the full grid is 2.4384 m x 2.4384 m x 2.4384 m
Floor unit is best becuase it is very standard and made the size it is for character collision issues.
So:
Floor in English units should be 8'4" x 8'4"
Floor in Metric units shouold be 2.4384 m x 2.4384 m
Character, I believe I read some where that they are around 6'1" tall.
At that point you should be able to scale your units to match the floor.
Save the progect as a template to make your models from.
Hope this helps.
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