Hi AtHomeSewing, I got your email but could not reply to directly to you regarding barker cabinet drawer measurements. hope that helps!

i measured my drawer bases for you. here is what i got:
all my cabinets are 34.5" high including a 4" toekick.

4-drawer base:
the three bottom drawers are about 8" high. the top drawer is 6" high.

3 drawer base:
the two bottom drawers are about 12" high. top drawer is 6" high.