The 'nut stranglers' do the check 'A' at base/ maintance organisation and sign for it, pilot does his own check in as much or little detail as he/ she wishes. Pilot not allowed to do check 'A' at base/ maintance organisation if they are at the same location if that makes sense.
Away from base/ maintance organisation pilot has to do it, of course a check 'A' authoristion has to come from the maintance organisation for the pilot so that means you can end up with having to do a check 'A' run around with an engineer for the same type of a/c but different a/c maintained at different organisation.
This is AOC, UK, JAR, EASA or what ever we are on today which is standard stuff, so at base you come in check paper work walk around a/c looking for the obvious, wouldn't start un-doing anything, you have to trust the engineers.
Unfortunatley '**** happens', and every now and then your most trusted engineer makes a mistake, well he's not a pilot
, didn't say it was a good thing.
Best wishes to the pilot.