I managed commercial construction projects for many years, have built and remodeled several properties, and never once have I encountered any of these scams. The tone of this article is deeply troubling. The author seems to be saying that ALL painting contractors are inherently dishonest, and that has not been my experience. The underlying advice here is sound: get it all in writing and cover as many contingencies as possible--so pointing out potential pitfalls like coat coverage is helpful. But do that in the spirit of clear communication of expectations, not with the expectation that the person you are hiring will try to cheat you at every turn. Not every contractor takes outrageous advantage of change orders; not every contractor will sneak past necessary preparation and/or repairs. Contractors of all sorts get a bad rap as it is; reinforcing a stereotype with articles written from this point of view just seems unproductive.
I've seen this article sent out 4 times now. It's out dated in terms of today's "Scams." Paint stores haven't charged more money for deeper paint colors in over 15 years. Also Water downed paint? Seriously? That would never happen in the real world. And Wall repair? what painter would ever not assume wall repair as included? This article is a waste of time and should be taken down or edited to reflect actual scams of todays times.
Some contractors work on time and material others on a firm contract. I would never hire the former and am leary of the latter. A contractor may low-ball a bid to get the job planning to make a killing on change orders. If you say good morning to them, they charge you extra for that. If the contract is not very, very specific and extensively fleshed out or if they display their change order schedule prominently on top, show them the door.