Putting car on the lift, removing under panels, removing all drain plugs in a specific way and draining the oil step by step at these points, and everything back on including oil fill in seems to be more than an hour of work. I believe they know the car a little more than I do so checking the points where they probably had a problem with another cars as well as driiving it to recognoize anomalies we don't seems to be a good idea. Also 1 litre of high quality oil is around $28 here while the oil filter is a cheap $18 thing.

And on my Spyder it's even another story as the filter sits underneath the tonneau for the top. No idea what it takes to get to that damn filter...