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$400-500 is possible, but I wouldn't get it online. Visit several local paint shops and go with the people that seem most knowledgeable and willing to help. You'll save shipping and should have plenty of options. You can do this in two days if you stay on it. Don't skip high build primer and wet sanding that with a guide coat--its the difference between a crap job and something decent. That'll have a bigger impact on quality than the choice of paint.