Candleshoe (1977) on Netflix

Small-time crook Harry Bundage discovers that the old manor house where Lady St. Edmund resides, with three orphans and her butler Priory is the resting place for a hoard of treasure. Unfortunately, he doesn't know where it is. Bundage recruits urchin Casey Brown to dupe Lady St. Edmund into thinking that she is her long-lost granddaughter, so she can search for clues to the location of the treasure. Unbeknownst to Bundage AND her ladyship, Lady St. Edmund is flat broke, and Priory and the children help her ladyship try to keep her home and pride. Joined by Casey, they do all the chores and Priory acts as the butler, gardener, chauffeur and an old major all at the same time!