I have a question about how to select a stain for both exterior and interior doors which are Meranti. I wanted the finished colour to be Rose Mahogany, but does this colour have to be made at the paint desk? There does not appear to be any on the shelf. For interior doors, I'm planning to use Cabot's Interior Stain Oil Based and a clear OB varnish. For the exterior door and panels, I'm planning to use Cabot's Deck and Exterior Stain OB. Do both of these products get mixed for you at the paint desk and should I start with a sample pot?