Ideally I recommend testing colours on the wall before any painting.
We need to look at the colours in our space in the morning, at noon and in the evening and on different types of days: sunny, rainy, etc.
I recommend buying one litre of paint to test the colour. Some companies now offer small tester formats. Two coats on a 3 foot by 3 foot surface are enough to give an idea of the final colour. It is always possible to use a few samples of the same colour on the wall to visualize the effect.
Once they are applied, colours take an average of two weeks to attain their real tint (depending on temperature and humidity).
Buy quality paint. Your eyes, your nose and especially your painter will thank you.
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