Surely it would be prudent to get them to reverse mortgage some of their assets before sucking the public teat. Otherwise there is a massive disincentive to save.
So, you'll tell the old couple/widows that they can't get the pension and need to take out a very-expensive government reverse mortgage, because the house in which they are living has appreciated a lot in the last 40 years.
Once said mortgage is taken out, they can't pay it off without selling. So, even when the equity in the house has fallen to levels that you deem acceptable to get the pension, they still need to sell the family house to be able to discharge the mortgage. Meanwhile, people in adjacent suburbs are allowed to stay in theirs.
While I'm sympathetic to the argument of who should access public finances, they're just playing by the rules. Coming along after the event and moving the goal posts is bloody rude. There're a bucket load of things that could be changed, policy-wise, but it's almost impossible to do without screwing people at the pointy end of the game.
By the way, I don't ever expect to get the pension, so I'm not bleating about my own privileged position.