Is there a way to complete Sarah's quest for the achievement without spending all my sP? Also, what is the point of Alchemy Tokens? I have also seen minions labeled as Alchemy lv -?

you can do Sarah's quest if you create a forum group and deposit your sP in it, you can retrieve it anytime you want

alchemy tokens are used for alchemy, here's a guide for it: xxx

every item you can make with alchemy has a "Alchemy Level:" which shows which alchemy level you need to be in order to craft them

Thank you. I've been semi-in and out of the site, so I missed a lot of feature changes.