I just restarted a character and forgot how weak we are and how hard it is to make money. 100gp for a healing spell is a lot for someone who tries to not kill anyone, and rats do not drop coins, so my suggestion is to make a npc giving you the task to kill them and rewards you with some coins.
I might fall into current MMO style but recycling items, I don't know, maybe 100, could give some experience just for the fact that you are doing a good deed by recycling (could be a low level deed/quest only).