When we bought our first home in Ottawa, we were told by some of the neighbours that the previous owner was a she bear on getting work done properly in her home. She supervised workers directly and watched that the job was done right - right according to her very specific and demanding requirements. That was a lesson to learn. There should be no shame in being home when work is being done, watching that the materials you wanted are used, that the workers are doing the job you are paying them to do.
In that home, we had a water flood that destroyed the hardwood floors. We hired a well known company and then had to move out when the floor was being installed. One night, just before the top varnish (?) was to be applied, we walked back to our house to check. There were two workers, sitting in our kitchen, feet up on the chairs, smoking. The windows were open and the floor sanding dust was swirling. WE SHOULD HAVE STAYED!!! After they went back to work and we left, they applied the sealant OVER the dust. They never swept or vacuumed it up!!! We had to complain. The floors were touched up but, unlike the previous owner, we never got the quality of work that we wanted nor the floor that we thought we had paid for. When we sold the house, I still was telling people of the very poor service we received from that company.
If you have work being done in your home - stay around to ensure you are getting what you want and what you paid for. If you can't do that, try doing some of the work yourself. We are our own worse critics and it is likely that the work you do (even if it is just to prep the house for painting) will meet your high standards.
Photo credit: Following Hours of Sanding