Request #418 From Kathleen

I’m looking for a British YA book from the 70s or 80s. A young couple gets married and lives in a flat in an apartment house in London filled with lots of different characters. I remember they were always looking for change to feed the heat meter to stay warm. She gets pregnant and has a baby boy and when her very uptight mother comes to visit all of the neighbors bring them furniture to make it seem like she’s got it all together. Any ideas?