Wes & Kit
Robert & Louie
Mystery at Skeffield Manor
These three books take place in the same universe and may or may not have some of the same characters, but are independent stories:
Like A One-Eyed Cat
Cold Hands, Warm Heart
I also started a connected series (only one book so far) with more of a focus on the magical elements of this universe:
Forgotten Things (Men of Magic book 1)
The heat levels of the books vary, but most are pretty low, in my opinion. :-) Many of them contain some sort of mystery element.
Trivia: The first one I wrote was Like A One-Eyed Cat. I wrote it in a very brief time; it just poured out of me.
I realize that gay romance mystery steampunk is not a hugely popular genre, and I wrote these stories because I felt passionate about this world and the characters in it.
I don't know if I'll write more or not. I feel like I've completed the four-book arc that started with Wes & Kit. But I hope to write some more in the Men of Magic series set in the same world, and there could always be further steampunk romance standalones that don't necessarily connect closely with the other stories.