"Polish" property was doubtless owned in part by Jewish families and so we're back to square one in terms of the entire question of reparations!
The matter is more complicated than that.
First of all, in pre-war Poland Polish Jews very often bought real estate on credit in Polish banks
, like the biggest bank in Poland: PKO Bank Polski. Most of that credit was never paid back
to National Bank of Poland [PKO] when WWII broke out.
So the price of unpaid credit should be deducted from the sum of a final reparation.
Furthermore, almost all real estate in Warsaw (and to lesser extend in other big cities of Poland) was destroyed during WWII and rebuilt by Poles after war
This should also be deducted from the sum of the final reparation.
In many cases the sum of deductions would exceed the value of a lost property.
And obviously I'm only talking about rightful claimants, that is those rightful claimants with all the proper documents and not some NGO's like World Jewish Congress with absolutely no rights to claim any reparations from Poland.