Hmmmm, I think people are confusing things a bit if these timeshares were dropped into a Living Trust, which would have ownership of the timeshares and be responsibile for maintenance fees. The Living Trust, which would likely become an Irrevocable Trust after the grantors were no longer around, would have a Trustee responsible for the mainenance fees and actually the timeshares would be owned by the Trustees as fiduciaries of the Trust. My wife and I have a Revocable Living Trust, which will morph into an Irrevocable Trust, when one or both of us are no longer around. Real estate in the trust, like other property or assets funding the Trust, is handled by the Trustees, my wife and I initially for our RLT, and then if were not around, successor Trustees.
If you want timeshares to be handled by your "estate," you should set this forth in your Will and leave them out of any Trust. And your Wills could name an appropriate beneficiary for the timeshares, but as others have said the beneficiary could disclaim or renounce the transfer and then the Executor of your estate would be stuck with handling the timeshare.
My wife and I are grappling with this situation ourselves, with our children not firmly committed to wanting our timeshares. One solution is to place the timeshares in the Living Trust, and the Trust would have to pay maintenance fees -- with a decent level of liquid assets in the Trust -- the payment of maintenance fees shouldn't be a real burden for the Trust and the Trustee could be given instructions to administer the timeshare for benefits of the children. This arrangement can go on indefinitely, but you'd have to have a willing Trustee to do this work, which would be the same work you're currently doing for yourself! The Trustee could also, if no one is using the timeshares, sell or gift it
away.
If your children don't want anything to do with these timeshares, another solution is to have a Transfer on Death Deed for the timeshares. This Deed would transfer the timeshares upon your death to specific people, like Steven or me (LOL), and bypass probate or estate issues -- many states permit this type of transfer for real estate, stocks or bonds, including, perhaps California, where these timeshares are located. Of course, the beneficary/grantee of this Deed might also be able to renounce or disclaim ownership.
I think the best solution would be to handle these timeshares while one is still living and try to have Marriott re-purchase them or sell them on the open market. In our case, we have transferred or funded alot of stuff in our RLT, but our timeshares are not one of the items we have placed in the Trust.