hi, just wondering how do people ensure the plaster ceiling is even across the whole stretch, do you guys use some sort of measuring tools to ensure they are flat? some places the ceiling itself aren't exactly 100% flat so how do you guys adjust them?

also for cutting light holes, how do you ensure they are in light with each other? so they look neat & evenly apart?

Hi do the plastic ceiling quotation normally include skimming. My id is quoting it separately in the painting side.