How much do Personal istants usually make?

I would love to start my own business and the right job for me would be a Personal istant (part-time that is) that will run your errands, do your laundry, type a letter, make a payment, pick up kids from school, do light cleaning, filing, etc...Im trying to brainstorm ideas as to what my rates should be, how should I charge them? (by the way these would be like temporary jobs where a family can hire me to run errands either everu other day in the morning, another family coud hire me to do their laundry at noon and fold their clothes before they get home from work etc ) HELP! Asnwers from past personal istants would help so much!