His client isn't happy with the stain match of two different species. What should he do?
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Samples. I've used the same stain on the two separate woods with different application methods on the samples on the birch.
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It's like every time I use the same stain even applied. The same way with preconditioning, the color turns out different.

I have Alder cabinet doors, and the facing of the cabinets is birch. How can I match the stain on the two different woods? Additionally, where can I find a dark caramel color for these two? 

Our clients are not happy with any of this. Some of it matches pretty fine, but that is not the color they want. They want a dark caramel, but I can't find that color. 

Please help!