Looks like it's a Ka
http://www.theanswerb.../Question1121335.html
In which case an oil filter should be about £10 I'd think say £25-30 for the oil ( and that's steep), Air filter say £10-15
The rest is just an exorbitant hourly rate to inspect brake wear and various other parts
Probably charging you £200 an hour for 30 minutes work at a guess
Ask around to get recommendations for local garages near you - the main dealers are trying to profit from your insecurity.
I'd be amazed if you couldn't halve that price