In some cases, professional painters may include additional charges for specialized equipment that homeowners can't purchase on their own. Because professionals have licenses and access to such equipment, it's simpler to let them get those themselves. But providing some of the smaller equipment and extras directly really can help to cut down on the total cost of your project.
Sorry it is difficult to trust almost anyone in the trades. It is easier to do the work myself and not deal with strangers in and around my house. When I have to hire someone I tell them up front that I'll be checking every detail, pay extra to purchase the materials myself, and if they don't want the job - well good! I always fine someone who will work with me as I pay a bonus for that.
Painting contractors must also carry out administrative and marketing duties. They prepare final accounts for customers based on the original estimates and any additional work. They analyze the cost of the job compared with the estimate to calculate their profit. They market their business through activities such as setting up websites, asking customers for references or contacting property maintenance companies with details of their services.