How much of the ?300 is parts and how much labour?
I don't have a clue how the price of the belt compares to a conventional chain, but iIt seems expensive to me.
This suggests changing the belt is a 45 minute job, so either they have hourly rates that would make a Ferrari dealer blush or the belt is very expensive.
8000 miles would be extremely poor from a chain - I thought one of the advantages of the belts was long life?
Tell her to sell it and buy an SV650
EDIT:
Clucking bell,
this shows a belt price of ?155! Cheap Korean bike is not so cheap to run. That still means ?150's worth of labour which is excessive if it's a 45 minute job.
I found a
service manual so she can learn to do her own spannering