Charging for food for an adhoc mindee

[sassyminder]

Hi. I look after a child whose parents provide food and now they asked if I could provide it. The answer is yes I can but I dont know how much should I charge extra? My fee is £6/hour (London) but the child comes randomly, not two weeks are the same, he could come 15 hours on one week and 40 on another...
Any suggestions?
Should I set a price per meal + extra for snacks?
or a fixed weekly fee, which would be a bit unfair maybe but the facility to have their place available no matter how much needed is sure priceless, since they just pay for booked hours and dont pay retainers nor even when they go on holidays...

If they just pay for care by the day, then I would just charge for food by the day.

I would use school meal prices as a guideline for dinner/lunch ... it's about £2 each but check local schools. With snacks ... depends what you give for snacks but I think 50p should more than cover it.
Btw ... you're so lucky to be able to charge £6 and not include food ... I'm on the edge of London and our prices are nowhere near this but still inclusive of food.

I just ask parents to book/cancel meals at least 7 days ahead, so I can plan & shop.

breakfast £1.50, lunch £1.50, dinner £2.00. No reductions or refunds if the child doesn't eat the food provided or is absent with less than 48 hour notice.

I used to charge £2.50 for lunch, but nothing for snacks. That was a few years ago. Depends what kind of food you are providing.