I've tried searching for this in all forms but apparently I'm using too many common search words, so I'll have to be annoying and ask on here

I was wondering what the average rate a child extra would be paid and also if they wouldn't allow a child extra to attend alone (ie. without an adult/parent dropping them off - I'd be going on the train)!
I'm not asking because I'm 'obsessed' by money/pay in any way, simply to see if something would be cost effective?!
Many Thanks.
XXX