Royalty and free to play games

Hi guys and gals, my first post on theese forums.

I want to check if my understanding is correct.

Let’s assume that I have some game rolling that uses free to play model: people don’t pay for game itself, but they pay for some extras in the game (appearance, boosts, larger limits for different in-game limitaitons, etc.)
For example, over a quarter 100 people “bought” the game, 10 of them bought a glowing hat for their character 5$ each and 3 of them bought inventory expander 10$ each.

So my gross income for month will be
0100 (game itself)
10 (5 glowing hats)
10*3 (3 inventory expanders)
= 100 + 50 + 30 = 180 $.

In the end,
I’ll have to pay
319 (subscription for 3 months)
0.05 (loyalty)
= 66 $ total for recspective quarter to Epic.

Am I correct?

Thanks in advance.

P.S please do not discuss the healthness of free-to-play model here.

Yes, but don’t forget you won’t have to pay for the subscription again in the next month, so it’s kind of weird to include it in the monthly calculation. The subscription fee is a static cost and it should be taken from the total income your game will gain you during it’s entire lifetime.