I Capture the Castle, a book by Dodie Smith I read a long time ago and had completely and happily forgotten, so it was like reading a new book except I knew I would like it. It has one of the best first lines: "I write this sitting in the kitchen sink."
Although the setting is romantic - a ruined castle with a poverty-stricken family whose former bread-winner has writer's block - it is the story and developing character of the narrator, 17-year-old Cassandra and her family which is the point of the book. Cassandra writes in her journal what happens when the family, at their wits' end regarding generating enough income, meet a rich American family who have inherited the local stately home.
Cassandra's older sister Rose is determined to marry for money. Stephen, almost adopted brother, has fallen for Cassandra. Topaz is the passionate 'muse' and ex-artist's model who makes for a wonderfully eccentric stepmother.
What I like about these characters is that they are rounded: although Topaz, for example, goes naked in the rain, she also is very practical about cleaning the house. Rose isn't completely mercenary either, and Stephen ends up doing something completely different from what you'd expect.
I also loved the description of the seasons in England, and the atmosphere of living in a moated castle. Also the impression that England and English have on the Americans; Dodie emigrated to the USA from England, so she knows: one American says that fall is melancholy here and it isn't in the States. I have had that difference in feeling too, though mine was the other way round, maybe from homesickness.
And then Cassandra falls in love... you'll have to read the book to find out what happens then.