Do you mean that if a bandit or a murderer steals your house deed, it is gone? And he can use it himself?
if I have set the house deed, can enemy players destroy the unfinished house?
If you get killed on the way to place the deed then it is in your loot.
I actually was careless and lost the first deed I tried to take out.
My loss but I am sure it gave the player that killed me an unexpected surprise.
I just started over and had the house built a couple days later.
When you first put the house out it will not have as much hitpoints and you will have to pay upkeep.
Not sure exactly how much it took but I had to put in a bit of mats before it would allow me to start building.
So be prepared with some mats and a little silver to get you started.