I have heard salespeople use a sales technique or warning you that you need to buy sooner than later because "your trade-in is depreciating," but so what. An older car car does not depreciate at nearly the same rate as the new car you buy will. If your trade in is already several years old, the value won't change much even in 6 months. The money you save in the meantime (not making the new car payment etc.) by waiting can be used to have a bigger down payment and finance less on the new car later. You will save more than the value of your trade-in will decrease.
For a new model like the 2010 Prius, the market is being born. The initial price is Toyota's best guess at the MSRP price point that will profitably match supply and demand over the longer term, taking into account the multiplicity of factors that go into the pricing. There will be short-term variations; one of the biggest unknowns is what happens to oil prices as the world economy recovers. If oil prices head North with a vengeance 6-12 months from now, demand for the 2010 could rapidly outrun supply, resulting in dealer price escalation. In which case, waiting to buy might not look so smart a strategy. As always, timing is everything.
That is true Web1b. But what if your trade in has some sort of problem in those 6 months. What if the ECU goes out. Surely you don't expect the dealer to give you the same appraisal after 6 months and a bad ECU. I'll be the first to admit that it doesn't happen often. However, if it does happen, well, it wasn't smart to wait the 6 months. Again, so there is no thinking I am playing some "salesman game". It happens rarely, but I have seen it happen.
I have had salesmen use this technique even when I will be ready to buy in a week or two and just need to shop other vehicles first. If I don't want to buy for six months, then I won't waste time getting an appraisal quote for my car or asking for any information about pricing and probably wouldn't even talk to a salesman that far in advance. Right now, I have a pretty new car that is actually depreciating somewhat every month, but is still under factory warranty so I'm not worried about repairs and the biggest depreciation hit has passed. It usually doesn't make sense to trade-in 1 and 2 year old cars or you don't get your moneys worth out of them.
You would be surprised how many people come out 6 months in advance. And every salesperson thinks the same thing. Why on earth would you be out this soon. And I agree 100% that it is not worth trading in a 1 or 2 year old car. You have just eaten the 2 biggest depreciation years and then trade it in? Makes no sense to me either. If you are trading in within a week or two, then the depreciation scenario doesn't make sense at all. But we hear it all the time that "I will be ready within a few weeks" and see the customer 5 months later.