I am going to play devils advocate here and suggest the reasoning behind the fee. Please note I have no idea why they would mention a leak and suggest an oil change. If the leak was minor they could have waited until you showed up to collect to notify you.
But onto the charge for the oil change. (my best guesses based on running companies for many years)
The vehicle has to be on a lift usually to perform the oil change. That ramp if being used by your vehicle cannot be used by any other vehicle. Hence the 1 hour charge.
They have to give a quote up front so they base it on worst case (on average) over all vehicles they perform services on. They probably charge by the one hour block for lift work as some jobs will run long and some will run short.
They will book 8 (slots) per day. If a job runs short they may at the end of the day have enough time left over to advance a job from the next days work. But they may also free up some time for a job that ran long. It is a balancing act.
As to why they didn't give you a discount on an oil change as you were already on this lift. That would open them up to arguments with customers. You in passing tell someone they did an oil change for £30 which was discounted due to you being on the lift.
They go to get theirs done and are charged the full £60 and they get into a stroppy argument about why they did it for someone else for £30 but not them? Sometimes keeping to a strict and stated price list prevents future issues/arguments.
edit: An oil and filter change is usually 30 minutes or so. But you have to anticipate the problem ones where the plug is cross threaded and jammed in for example. Or the oil filter hasn't been fitted correctly and takes a monstering to get out.
But onto the charge for the oil change. (my best guesses based on running companies for many years)
The vehicle has to be on a lift usually to perform the oil change. That ramp if being used by your vehicle cannot be used by any other vehicle. Hence the 1 hour charge.
They have to give a quote up front so they base it on worst case (on average) over all vehicles they perform services on. They probably charge by the one hour block for lift work as some jobs will run long and some will run short.
They will book 8 (slots) per day. If a job runs short they may at the end of the day have enough time left over to advance a job from the next days work. But they may also free up some time for a job that ran long. It is a balancing act.
As to why they didn't give you a discount on an oil change as you were already on this lift. That would open them up to arguments with customers. You in passing tell someone they did an oil change for £30 which was discounted due to you being on the lift.
They go to get theirs done and are charged the full £60 and they get into a stroppy argument about why they did it for someone else for £30 but not them? Sometimes keeping to a strict and stated price list prevents future issues/arguments.
edit: An oil and filter change is usually 30 minutes or so. But you have to anticipate the problem ones where the plug is cross threaded and jammed in for example. Or the oil filter hasn't been fitted correctly and takes a monstering to get out.