I think it would have to retail for at least $499 for Sony not to lose money on it. Remember, the retailer's taking a cut, and there are distribution and manufacturing costs over and beyond the component costs. I'm not even sure that they would truly break even at that number. but, I imagine a real break Even is somewhere around there.
As for what the cost will be, I expect it will be $499. However, it wouldn't surprise me to see $399 either, especially if MS launches Lockhart this year.
The big question mark that's been thrown into all of this stuff is the virus. is this thing going to totally destroy the world economy? If so, how many people are really going to shell out $500 for a console this year?