I did this when I was a young ECE and $$$ was more important to me than family time ... I charged $8 an hour for normal night and $150 for New Years Eve and that was 20 years ago ...mind I worked at a University daycare and clients seeking service were dual income professionals who could afford to invest in an adult babysitter specially who knew they child.

One of my peers got $500 for a 1 overnight weekend so drop of Sat am and pick up Sunday after dinner from one of them!!! Sweet money back in 90s