I've got a fourth book on mine:
Mystery:
The Dead Key by DM Pulley.
From the editor:
When engineer Iris Latch gets her first field assignment out of college, surveying an abandoned bank, she’s just looking forward to a break from her cubicle. Instead, hidden among cobwebbed desks and dusty files untouched for twenty years, she finds hints that something rotten used to go on in the back offices. She comes to believe that someone else, a young secretary named Beatrice Baker, may have left those clues on purpose—and at great risk to herself.
The “dead key” in the title can grant access to wealth and forgotten secrets, but for me, the most valuable thing it unlocks is Iris’s connection to this young woman from the past. They share a lonely but fierce spirit that won’t let them step aside as corrupt and powerful men go unpunished. Their stories intertwine even though they don’t know each other, and in a strange way, they are counting on each other to expose the truth at last.