I’ve rated all the books individually, but on average it would be approx, 4 stars.

Murder at the vicarage: 5* - the first time I read this book was on audio, I gave it 3 stars back then. I suppose I must have missed a lot of the details.
The body in the library: 3* - I didn’t like the characters as much and the climax was a bit confusing to me. Also, I predicted the outcome partly.
The moving finger: 4* - I didn’t really like the way the story was told, but the plot was really good. I didn’t see the ending coming.
A murder is announced: 5* - this one was so good. I didn’t see the end coming and the whole story was so suspenseful.
They do it with mirrors: 4* - I liked it, the story and storytelling was good, but the characters were sometimes a bit annoying.
A pocket full of rye: 3* - I wasn’t quite feeling this one, but I still enjoyed it.
4:50 from Paddington: 5* - I enjoyed this one a lot and I definitely didn’t see the ending coming.
The mirror crack’d from side to side: 4* - it was nice to be back in St. Mary Mead and once again, I didn’t see the ending coming. I keep guessing, but so far, I’ve only been right once.
A Caribbean mystery: 5* - okay wow, this one, I really really did not see coming. And also, I loved the scenery, I wish I could go on vacation to the Caribbean too.
At Bertram’s hotel: 3* - didn’t like the storytelling in this one and the ending was super unsatisfactory.
Nemesis: 5* - this one was sooo good. I loved the storytelling and I loved how it sort of was a continuation on a previous story.
Sleeping murder: 5* - this one was so intriguing and suspenseful and once again I couldn’t guess the ending.
Miss Marple: the complete short stories: DNF - I stopped after the fifth, I didn’t find them the least bit interesting.