I'm not sure I follow. Pessification of real estate wouldn't necessarily change the value of the house. Now taking those pesos and trying to get them out of the country to use elsewhere is the real matter.
As others have mentioned on this forum, the peso is a bit like store credit, it's good now, but if you don't use it, you lose it... and it's not good anywhere else. Would pessifying the real estate market change that? I doubt it.
Your "investment" should be fine as long as the economy or real estate market doesn't completely tank (and in that case it doesn't matter if the price is set in dollars or pesos.) Look at cars. You buy a car today and next year it might be worth more than what you paid - USED! Nobody considers a car an investment, but depending on when you buy, it might as well be.
In any case, if you're living in your house and using it, then it's not necessarily an investment... it's your home. No matter what happens to the peso you will have your house if you own it outright. There might be an eventual hit to home values (or they may rise, since pesos are much easier to get here than dollars), but eventually prices should settle down and adjust to the market (and whatever is going on in that moment) even if they have to be updated on a monthly basis. Argentina is volatile, that won't change unless the whole economy changes.
Of course none of this would be an issue if the peso were actually trustworthy.
Fiat money has no intrinsic value; it only has value at all because all participants in an economy agree to trust the government issuing the currency.
And who can trust the Argentine goverment?
EDIT : I see the point now. Yes, cashing out here is difficult to do... especially during these times. But considering that Cristina is so antagonistic towards Europeans and North Americans, I doubt expats or foreign investers are high on her priority list. History has shown the Argentine government has no respect for savings or people on fixed incomes, either.
When you sell you need something else to put your money into or someway to get it out of the country... yes, that is a problem.