It depends on cost of living. The median salary for the county I live in is about $23,000 per year. Of course, a lot of the daily expenses are cheaper. Our entire family's yearly salary wouldn't even cover the rent in a place like San Francisco.

I've done the 2:30 AM service calls. I hated every minute of them, but they did pay well. If you're up to it, and can get it all done, total care can do well. Out here, it's 50 miles each way on a service call. Few places are willing to pay over $100 for a guy just to show up.