Interior painting and exterior painting is definitely a skilled trade. Like any other trade or skill, it takes time to develop painting skills and speeds not to mention better quality than the average novice painter would do.
A professional painter will be able to do the job much faster and neater than your average homeowner. There are plenty of techniques that painters use that the average homeowner wouldn't know or use. You can hire the best commercial painting service provider in Toronto
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To start with a professional painter will know how to do proper paint preparation for the walls and trim. He will have experience in repairing small holes all way too large ones.
Small holes just about anyone can fix properly without too much trouble but the problem is that if there are large holes in the wall and it is not repaired properly it will create a bump or hollow in the wall.
An important thing to remember here is that the painter is more equipped to do such repairs because he does this all day long every day so when it comes time to do these repairs he has all the proper tools which the homeowner might not have such as special plastering knives and proper means of cutting drywall to correct dimensions.