As far as real estate landmarks go, this Bethesda, Maryland home is a winner. This unique 4-bedroom home with high beamed ceilings and an in-law apartment has more nicknames than the roster of a professional sports team. Locals alternately call it the “Mushroom House,” “Flintstones House,” “Hobbit House,” “Blob House” and “Smurf House.” Based on a quick glimpse at the…