I have been a nanny for over 17 years and I usually charge only if I am expected to drive more than a certain amount of miles per week. I discuss this with the clients during the contract negotiations unless it was a sudden change. You can figure out mileage reimbursement very easily by referencing IRS.gov. According to the IRS the 2018 rate per mile is 54.5 cents per mile. I keep a detailed calendar and at the end of each week I calculate the mileage using the GPS on my phone. So if I drove 200miles I would multiply that by .545 cents which would come out to $109. This seems like a lot but that includes your cars maintenance, gas and insurance costs. This is a reimbursement so it is NOT TAXABLE INCOME and will need to be paid to you separately from your regular wages. Or you could work out an agreement that suits your needs. I hope this helps.
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