They support what's at risk (6)
I believe the answer is:
stakes
This might be a double definition.
'they support' is the first definition.
The answer and definition can be both related to property as well as being singular nouns.
Perhaps you can see a link between them that I can't see?
'what's at risk' is the second definition.
(I've seen this in another clue)
Can you help me to learn more?
(Other definitions for stakes that I've seen before include "Pointed poles or bets" , "Amounts bet; posts" , "Monies risked on a gamble" , "Sharp sticks or bets on horses" , "pickets" .)