It is difficult to calculate the "cost" of an F-22 as it depends on what developmental costs are included. A common way of calculating this is to calculate the total expected life-cycle cost per unit.
The GAO has listed the life-cycle cost of the F-22 at $469,000,000 per aircraft.
I think that is way too much to pay for a single aircraft. Half a billion dollars per aircraft? Yikes!
Here is a disturbing thought. The F-22 became operational in Dec 2005. Since then, we have had air operations in Iraq, Afghanistan, Libya, and in other conflict zones. Pretty much all of our operational fighters have participated in these actions. But not the F-22.
An aircraft that has been operational for 6 years, during which time we have been in a constant state of OOTW and no combat sorties.
Half a billion for an aircraft that has not fought and does not seem expected to fight in the near future. That's a swell deal for the taxpayers.