these are a few fragile figures with issues;

-G1 kickback-yellow insect/robot ears-Bp/fragile parts

-G1 megatron-shoulder joint sometimes has brittle plastic where the shoulder socket screws into the arm(silver)

G1 jetfire-red arm weapons have Bp clips,beware some try to sell these parts with broken clips as "mint"(ebay o/s)
-jetfire has BP around plastic/metal shoulder joints(where the jet folds in half to make back and chest)due to incorrect movement
-jetfire is prone to stress marks on the black antennae on the robot's head due to incorrect movement.

G1 soundwave and blaster prone to broken cassette eject button/latch/door(not the case w/mine!)

hope this helps!