i doubt dealer cost is 400 because they're being sold online for 450 all day.I think that website was bullshit, cause last time i checked dealer cost on those amps were like right at 400. I don't think anyone could sell that amp for 280.
Thats because people who sell stuff on Ebay sell it for just above dealer cost. The reason i know how much dealer cost is is because I work at an audio shop and one the distributors I order from sell Crunch amps. Now people who buy from the manufacture get a better price. The distributor I called gave me a price of 450, I said $400 in the post cause i'm guessing thats prolly the difference from buying straight from the manufactuer.