Hi Kelly!

For your 72-inch vanity, here are a few size guidelines to consider for two separate oval mirrors:

1. Size proportion: A general rule of thumb is that each mirror should be about 2 to 4 inches smaller in width than the vanity sinks or the overall vanity width. For a 72-inch vanity, you can divide that in half to focus on each sink area, which would give you about 36 inches per mirror space.
2. Ideal width: Oval mirrors in the range of 24 to 28 inches wide would likely work best for a balanced look. This allows for enough space between the two mirrors without them looking cramped or oversized.
3. Height consideration: The height of the mirror is flexible based on your ceiling height and personal style. A mirror that is around 30 to 36 inches tall tends to complement a 72-inch vanity nicely. You can go taller for a more dramatic effect or shorter for a subtler look.
4. Spacing: Make sure there's at least 3-6 inches of space between the mirrors and the vanity, as well as between the mirrors and the walls. This will help create a well-proportioned and elegant layout.

Would you like suggestions on specific mirror styles or finishes to complement your bathroom design? Feel free to reach out on my Houzz profile!