hate to give away any secrets or make you feel bad, but i'm sure in that case, they didn't put "true value" as your trade value.
our list price is generally about 4500 over what we paid (all changes with crazy car values of course). figure, we allow for roughly 1000-1500 re-conditioning/safety/e-test, 1000 room to move on the price, 1500-2000 profit.
varies of course, but that's not too far from the truth... and makes sense...
say we offer 8k for your trade... we'll ask 12500... at the end of your driveway, you could try to get maybe 11 and not move much on price... so to compare, the trade was easy, didn't have to do anything to the car or deal with "buyers" and you got the equivalent of 9040... to safety and e-test and crap, take your 11 asking down to 10500 what you are netting.
so a 1460 difference in your pocket for the effort put in to sell it privately. sounds about right to me. some will see the value in selling it, others, its not worth that.
to each their own.