Hello Liz,
Welcome from the U.K, and sorry to hear of your issue.
We take it this has automatic transmission -?
Oil dripping from from front? or rear? would be useful to know, with front being potentially the worse situation.
Re costings - sounds about what would be expected, but you would need to confirm this includes? a gearbox oil change service, which in itself is quite expensive.
Perhaps you would fill in a little more detail.
Oh - severity of oil leak as is at the moment ? Is it ‘just keep an eye on it’ , or is it such that it must be done now?
Kind regards,
Gareth.