Caveat, the name I'm posting on has zero books out. It is for thrillers/crime fiction. I will go wide when I release them. Highly unlikely I will advertise. These will also be the first books I didn't do my own covers.
I have 2 other pen names with books published. Both are erotic romance. Any "advertising" I have done on my books was perma-free on serials (gawd I miss those days) or series, or shorts with the exception of three shorts/novellas that were translated last year and the translator was getting a cut as payment. I think it was $100 I did but I had the translator run the ads and didn't bother with looking at what the cost/results were. The translator already had access to far better places on FB to just drop the link. Translations came to approximately 3k gross revenue from the numbers below, most of it on Amazon.
One of the names (and I don't have the income split out) doesn't have any social media. Out of 11 or so books on the name, I have months where nothing for the name sells on Amazon. But it has mostly SF/F so I usually see sales on it on Nook. It also has the oldest, most meh covers from my being a DIY. Maybe this year I'll recover the books, tweak enough to warrant a new ASIN and publish them again.
Depending on the platform, I (eta my primary pen name) have 49 single titles from shorts to novels and 3 collections. Amazon has 52 plus 4 since I decided to try the translations in KU and that turned out to be a dead zone.
I am quasi active on Facebook, nowhere else in terms of reader outreach. I have a newsletter of about 600 subscribers after I nuked my last newsletter of nearly 6k because the rates were too low (was really stupid to nuke it). By quasi active, I interact with readers and other authors, but I think the most feedback I've gotten on a post was a non-book post and it was about 100 reactions, so, really, I suck at facebook. I will post about a new release usually only on release week. I only released 4x in 2018. Those new releases are about 1/4 or less of my 2018 income. The only titles in KU are the translations (again, that's a small part of my income and the page read money is minute).
Anyway--2018 numbers are my lowest since 2011. Assuming my records are correct, those numbers are as follows:
Nook 9019.52
Apple 4991.37
Kobo 4711.94
Google 998.22 (only has about 30 titles on it and I've been adding those slowly over the year, about 1/3 was from the translations)
Amazon 33846.8
I am a proponent of "passive marketing" -
genre (niche or big market that can sustain little fish),
description, cover (doesn't mean it has to be awesome, it has to be not ugly and conform to genre expectations),
title (the billionaire, the doctor, the mechanic, the cowboy -- can you have a normal length title but still have a crucial keyword in it?), and metadata (keywords and the already listed title).
I would add one more - consistency, but I am crap at that. Even when I was writing serials, I would do other books, sometimes longer books, in between the installments (and definitely so with novel length series).
I know people don't talk hard numbers a lot. It's "gauche" but I think advice about spending money should include real talk of money. Someone will come along and say "I make six figures a year because of my marketing." That's nice, but, please clarify. Do you NET six figures?
Finally - before you lay your $ down, consider this recent article. It plays to my confirmation bias, but even I found it eye-opening.
http://nymag.com/intelligencer/2018/12/how-much-of-the-internet-is-fake.html
