I'm hiring an interior painter and that is why I was reading this comment list. I'm concerned about your comment about Angie's List. Some of us don't have personal recommendations for tradespersons, and rely on sites like this. Are you saying that Angie's List's reviews are not complete or that they do not print some of the negative reviews? It's hard to know what to do - I have not been able to find a person who just had their paint done so I can ask him/her about the quality of the painter.
Back to the article. You can add water to all latex based paints / thinner to oil based paint. The tinting base has absolutely nothing to do with it. Say you are working outside and throughout the day you have to add a little water to keep the same consistency. If somebody really tried to add 20% to 50% water they no longer would be painting they'd be performing a whitewash or pickle finish.
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