I am most disappointed that our Teacher Institute did not allow for more time inside the mansion than the after hours tour that we received. We were able to take more time than the general public, but even at the slowed rate, it is often not until well after that one can think of questions to ask.
Still, perhaps it is inside the mansion that preservation is the most obvious. The Mount Vernon Ladies' Association desires the mansion be restored and kept in the same state it was in during the year of Washington's death in 1799, in spite of the many changes that were made in the 19th and 20th centuries. That means some of the colors and designs of the interior are very garish by today's standards. The pain seems thick and glossy, with bold color on just about every wall, but that's what the Washingtons wanted - and at this point, what the Washingtons want, they can have.