Could it be The Upper Crusts?

"The Upper Crusts

ITV sitcom. 6 episodes (1 series) in 1973.

Overview
The Upper Crusts

Lord Seacroft and his family have come across hard times and they need to adjust their lifestyles to accommodate their new circumstances"

Upper Crusts

From review on IMDB:

"I loved this show and can't understand why it had such short run and has never been seen since. Margaret Leighton and Charles Gray play an aristocratic couple without any money who have to leave their stately home to live in a council house. She ends up giving guided tours of her council house, grandly pointing out, "and this is the West Wing". She also takes a bus ride and then goes to the front of the bus as she says she always tips the driver. It is 33 years since I last saw this show so I can't really remember too much else about it. I do recall that she becomes a maid to the wonderful Joan Hickson which is terribly funny. I just wonder if there is anyone else who remembers this marvellous comedy."

Upper Crusts IMDB

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