but now we play nice with them and if they don't charge us for damaging drywall around boxes, we don't charge em for covering them up.

Huh? What reason would you have to damage the drywall around a box if the drywallers had done there job right in the first place?

Okay, maybe if we screw up and have to cut the wall up but most likely it's not us but another trade that damaged our work.

-Hal