The first paid jobs I had were all baby sitting, starting with neighbours and friends, gradually becoming a regular baby sitter for quite a lot of families. When I left home at 18, my younger sister just took over the lot. I was a temporary live in mother's help for a few months before starting student life which was a good way to learn a bit of independence under the guidance of another family.
I do remember feeling grown up when I got my first pay slip and then the first time I actually had tax deducted.