In my experience dealers ususally have a trade in price (which is higher) or a cash price (no trade-in ) which is lower.
Is this always the case? If so, should we all then expect to get the full market value for trade ins or will the garage offer less?
They offer less.... That's why dealers like trade-in (unless the market is saturated with second-hand car as it seems to be a the moment)...They sell you a new car full price and buy your old car way below the market value.
Is this a serious question?