First I think its unrealistic to think it will correct to 10 years ago values.
What I am trying to get across is that if values decrease, all values decrease, and while being unable to sell at value owed would have little to do with it.
Take a 500K value home (at peak) and let's say a guy owes 450K (90%). Lets say the home plunges to 400K in value (20%). Now the guy is upside down on the loan for 50K.
So can he sell for the 450K he has a loan for? Of course not. He's 50K down.
But... if he could afford the payment before the price reduced he can still afford the payment. Assuming he wants to stay and live in the home.
If he wants to sell he certainly can. Just at 400K (realizing a 50K loss on this home).
However whatever home he buys (higher or lower value) has now also been reduced by that same 20%. So it is all relative. He buys another home, higher or lower, depending on what he can afford and realizes the gain there that he lost on the one he sold. That's the equalizer and the part that many do not see.
Now if he bought that 500K home and really was on the edge on affording the payment, that was a poor decision on his part as he will now not be able to afford to buy something else and if he can't pay the payment he'll lose the house. That is called living within your means (or not).
Now if he bought the home to inflate and flip and not live in for any length of time, he's just in deep shit and made a bad investment. In my opinion its bad policy to play your home as an investment. Do that with rental properties or other stuff besides real estate.
Several different scenarios there.
when this is all said and done most of the country will have seen a 35-40 percent correction in prices