No direct criticism of you as I would have enjoyed the benefit, but basically the contractor overcharged on jobs for materials and brought home the excess. I once knew a contractor who had a stack of 4x8 sheets of plywood (laying flat) that was over 8’ feet tall that he had skimmed off various jobs over a reasonably short period of time.My neighbor yo the north is a contractor. He is flat out upside down busy. He does any of the work we have to hire out. They did the front of the house 2 years ago with the room addition. We knew the back needed done. so he started bringing home non-used materials from the jobs they were doing. I stored them.
Weather got us last year.
With his generosity and a couple of his crew working a Sunday all I had to buy was the membrane/nails/shingles. Neighbors taking care of neighbors.
I will be installing a new system in his house when they remodel at my costs. No labor.
Wait.....90 sheets.......
When we paid to have a room added on to our house as few years ago I noticed several large pieces of dimensional lumber ( 2x8/2/10/2/12 ) that the contractor was obviously not going to need to complete the framing. I insisted he leave them all on site and he actually got pi$$ed. I’m assuming he had a project of his own and had included some of the materials he needed in my job order.
Probably happens a LOT. Not saying contractors can figure board feet needed to the half foot, but. . . . . . . .