James Hoffman has a great video (or even series I believe) on "dialing in" espresso machines, definitely worth watching.
That's also my key criticism with buying subscription coffee, often they send quantities that are too small to get to a meaningful brewing routine. I've had a gifted subscription for 150g monthly, and I was going through 30-40g just perfecting the output. So by that time I was left with enough coffee for 2 weeks and had to resort to alternative sources.