Carnival of Souls
Low budget simple, eerie, and out of copyright.
A car accident has a single survivor, but life is not the same for her afterwards. The woman is a organist and the in-story playing provides some of soundtrack in-story in a very natural way. An abandoned carnival site is used as an abandoned carnival site that has an eerie appeal to our heroine. And nothing is quite normal outside of the carnival.
Four hot baths out of six.
Final thought: think of it as a twightlight zone story