Gypsum moldings are said to cost 11 yuan per meter. How come the boss who is responsible for the installation still has a loss of about 5% when selling the moldings? Is this a thing?

I am a professional installer of gypsum wire. There are two ways to install gypsum wire. One is to stick it on with quick-adhesive powder. The other is gypsum powder and glue. It can be said that gypsum powder and glue are better, but you have to use special glue. Other glues dry too slowly. If there is old powder on the wall when installing it, you must clean it up and then put glue on the picture. In the future, if there are any cracks, if there are window headers or wood, you will need to tighten a few screws and perhaps a few screws to prevent shrinkage and cracks