Yes unopened with a receipt
If it is open no
The answer is no on custom paint, but you may be able to if the can is in new condition and not used, some locations will allow it to be returned but if they do most will give you a store credit for the purchase of another gallon of paint....Good luck
Do you mean custom color mixes? You might, I've seen it done in the past. Only way to be sure is to try it.
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