Update - We Won!
Thanks to the advice received in this forum, I was able to stick to my guns and insisted my siblings share expense data with me. The title company is now going to divide the balance equally at 33-1/3% each.
My siblings folded like a cheap suit when they realized what they were doing was crazy. That would not have happened had it not been for each and every one of you responded to my question.
Thank you to all, you truly made a difference.
Rooty