You might be better off hiring a cabinet maker for a custom vanity. Sometimes it’s less expensive that way, if what you need is difficult to find. More on reddit.com

maybe slide it to one side make a 3 inch bookshelf with a toothbrush holder and other bathroom organizer stuff on it More on reddit.com

One sink! Extra counter space is so much more useful than 2 sinks. I can count on one hand the number of times I've been in the bathroom getting ready at the same time as someone else. But extra counter space is so useful for doing makeup, hair, products for washing face, towels, etc. More on reddit.com

Solid wood vanities are what started my journey into woodworking. A couple years later, I no longer want a solid wood vanity, but I've picked up a great hobby. OP - Solid wood warps, it expands and contracts with seasons. There are some that do this more and some that do it less, but it will be exaggerated in a place that gets frequent wild humidity swings like a bathroom. What doesn't warp seasonally is MDF, and to a lesser extent plywood, which is why a lot of high end vanities are still plywood casing with veneer, and solid drawer fronts. If you really want a solid wood vanity, paint or appropriate sealing will help, and so will buying one made out of a wood that is rot resistant and dimensionally stable. Things like White oak, Teak, Mahogany's, Cedars, etc. Just know that from a woodworking perspective, the MDF/Plywood + veneer case, is not really a lesser product. It's almost certainly cheaper, but it has advantages as well. More on reddit.com