you are a kit builder if
- You buy microballons in 20 lb bags and dope in 5 gallon containers (and dont ask about the 50 yards of spun bonded nylon).
- you ruined your wifes blender blades trying to chop balsa bits into filler dust
- in an emergency you used her best silk hose as covering material
-everything in the guest bedroom is tinted blue from the rattle-can painting when the garage was too cold.
- your scrap box is filled with old kit pieces you remade because they were wrong density, grain direction, or poorly cut.

However, if you have over 100 plans, you may be a scratchbuilder.