How to reply to questions about stereo cost?

How much did you pay for that? I could by a car for that. We already have a car.
You could send your kids to college for that much money.
My kids are lazy and stupid. They think they are gonna inherit the money I'm spending on this stereo.
What does your wife say? I can't hear when the stereo is playing.
It's already depreciated. I bought it used.