I have an alternate suggestion. A well-built cabinet with a 3/4" thick back can be wall hung as long as it is bolted to the studs in the wall. In that case you would need no legs, and cleaning the floor would be easier. You also wouldn't have to worry about finding the right height legs, either, as you could just decide how high you want the counter of the vanity to be and mount it accordingly. Just a thought....

It depends on the material of the top. Some stones and solid surfaces can be backlit nicely. You can mount your vanity at any height you please as long as it it isn't a public place subject to the ADA. My buddy Tom and I, along with our wives, visited Italy in 2011. I told Tom if he bought this glass piece from the Murano factory, I'd build a gloss black Corian Nocturne shelf for it. The strip LEDs tuck behind the front rail and are dimmable.

No photos posted... That said,the two sinks end up squished to the ends because of the drawer base, so you almost need 4 sconces if you want them symmetrical to the sinks. Same goes for pendants. Alternatively you can have sconces on the sidewall and a double sconce mounted in the center. Drilling mirror glass is easy enough for those that do it for a living. I’ve only seen one break during Install.

There are three issues you need to reinforce for in this order. As the wall gets heavier, you need to consider the second and third item: 1) Pulling off the wall. This one is the easy one to imagine, and is the only consideration in most cases with builder grade cabinet and countertops because they are relatively light. In this situation, either the vanity separates from the wall, or it pulls the drywall (or similar) layer away from the studs. Putting an angle iron bar below the cabinet, putting plywood blocking on/in the wall, puting a heavier duty mounting board in the back of the cabinet, using extra brackets to hold differnt parts of your structure together, using longer screws, wood screws, are all good choices to prevent an item from falling off the wall. 2) Pulling the wall out of shape / compromising it, or in a catastrophic case even pulling the wall down (unlikely but possible with enough weight and a poor wall). A wall is usually just a simple box made of 2X4 wood with studs, and it is put together with screws or nails, and then attached to the floor, ceiling and other walls with more screws or nails. Drywall or rock board is attached to to the face, and that gives it more strength. If you have a long or very heavy (like cement) countertop, or a stone sink, you will need more studs, or thicker studs, and they need to be attached very firmly with extra screws to the ceiling and other walls. Your blocking in the wall may need to be heavier/larger, and brackets heavier or more of them. 3) The last consideration is reserved for the heaviest of heavy items, and it applies both wall and non-wall installations. When you get into this territory, you should have an architect define or review the structural integrity of your plan before proceeding. Extra large stone, cement, or glass items (like large cantilevered items, glass doors over 6' wide, fireplaces, stoves, stone or brick arches, small pools/hot tubs, etc) will need extra support below them in the floor, so the floor doesn't sag below your reinforced wall. If your wall is on an upper floor, ideally it is sitting on another wall below it that will share the burden. If your wall is on the first floor, you could install a post in the basement level below it, if it is not already supported by something in the basement. If you have a very heavy item on an upper floor, and it is supported by a wall that has no wall below it in the floor below, it may be possible to put a steel beam in the floor to support the weight, or use special hardware to suspend the item from a steel beam spanning the top of the wall. Most of us will rarely if ever hit this last category,