But I'm looking to create a wide vanity -- 60 inches.
I have a small sink -- only 21 inches -- and I want a lot of drawers, deep ones on the left and shallow ones on the right. But a deep drawer, at 12" in width, is useless to me. I need a deep drawer that is at least 15", and preferably 18" wide.

I'm thinking that one way to save money would be to get a sink base with big drawers on the left and add a 4-drawer cabinet on the right. And I'm finally getting to the question. At what sink base cabinet width do they move into a wider drawer?

For example, if the line has 27" and a 30" and a 33" sink base, do you think they would all have just 12" drawers? At what point do they start putting a 15" drawer into a sink base? Is there ever a point where they use an 18" drawer in a sink base?

I also wanted decent drawers. Norcroft created it using 2 18" drawer bases and 2 21" full-height cabinets. The thing is, the drawers are so darned shallow their width means nothing.

I'm thinking of cutting out a mullion and putting in a bigger, deeper drawer. Width is one thing, but don't forget the depth.