In my flipping days I never bothered with MTBs or kids bikes, but I picked this apparently unridden Huffy "Iron Man" MTB from my neighbors trash, added new bearings and grease (for the first time in its life - it was assembled at the store sans grease), installed new ss cables & adjusted the brakes, centered the inner tube stems, aired it up, polished it up, and posted it for $35 on CL.

It made some mom and her little boy very happy = possibly my best flip ever.