No grade SS

Im a 18 lvl dwarf and about ro run out of free SS. I calculated that I can farm 7,7k adena (including mats price and quest fracions of quest rewards) in 10minutes constant farming and in that time use 4,5k adena worth of shop price SS. A friend already used all his free SS and it costs him more to buy them then he can even farm up. Does it get better in D grade or is it an everlasting trouble? I want to become a spoiler main but with this info I'd rather just make a crafter for my own SS and make a mage for my main.

Playing on Signature c4 x1 ofc