Hiya i'm a childminder and usually charge:
£3.50 per hr for a fulltime space
£4.00 per hr for a part time space (this is because even tho it is a part time space it also can take up a full time space as u may not be able to get another child to cover the free hours)
£3.00 to £4.00 per hr for an before and after school space and this includes the school run.
I also will arrange a sibbling discount normally £1.00 off the full paying price.
All these prices include meals and trips out.
Hope this helps hun?
You could also suggest to your mum that she advertises on www.childlink.gov.uk you can normally get on this by contacting the local early years department at the council.
There is also putting up posters in the local schools and toddler groups and she could also contact and join the NCMA (National Childminding Association) they tend to pass vaccancies round by word of mouth.
Goodluck xxx