Homemade chicken stock

This is my first time making stock. I'm making it in the slow cooker
using the chicken parts/"garbage" I've froze when making other dishes.
I've been collecting parts for a while and now I have enough to make
stock. I used to buy stock - waited when it was on sale, but still $2/
L. This homemade stuff is essentially free. Well, less than $2/L
anyways.