if it's double sinks, I'd have a mirror pver each sink.

I really like one over both - i'ts a bathroom of teen girls and it just works better when they're all doing make up in there.

Is it framed or frameless? I can't tell you how to frame it without knowing the style of the bathroom, but framing it is an option. You can use off the shelf trim.

Here is the vanity we are designing and the mirror:

mirror 70x36

and vanity - 76wide x 35 high

center the largest mirror to fill the space.

My question is - is this mirror at 70 wide too small for a 76 inch wide vanity.

Does your vanity have drawers on the end like the second picture?

Your other pic of your vanity is too small and dark to tell what the configuration is.

How far from the edge of the counter is the sink center and how long are your sinks?

Do you have a drawing of your cabinet layout?

76 inches minus 70" = 6 inches and divide by two equals three inches.

Do you really think the girls will be unable to see their faces with a mere THREE INCHES of drywall at each left/right side of the mirror? : )

Go look at your inspo picture again..... look at the sconces. Don't you think that might be quite a bit more than three inches on far left and right of those mirrors?

Don't wring a hand, right? Right. Center the mirror over the vanity and hang it: )

I like the idea the mirror will be just a few inches in on each side, will set it off nicely rather than everything being exact. You can easily draw the set up on paper and see which aesthetic appeals best to you.