The DCT was a $2,900 option on the 09s; think it was the same on the 08s.
Edmunds is a great source for pricing as is KBB. According to Edmunds, a CPO with the 18K miles, "Outstanding" (that is absolutely perfect condition with not the slightest blemish, tires with lots of tread) DCT, and options you listed (plus I added 19s, PDC, Sat Radio) is 57K. If this car has Premium Stereo that might
add another $500 to 1k so and that's about 58K. A "Clean" vehicle similarly optioned with same 18K miles comes out at just over 53K. Note: with 18K miles if these are original tires you're going to need new tires very very soon. The 6MT you mentioned, with other similar options and just 7K miles and "Outstanding" condition comes in CPO at 56K. So based on Edmunds I don't think the dealer is blowing smoke when it comes to the DCT higher-mileage car having a higher price tag. (Note: the numbers above are based on a CA zip code. You should re-run those numbers based on your region/zip.)
Here's the Edmunds link
. Here's the KBB link
. Go plug in your regional variables and the other exact details and you'll have some research to go in armed with. At least you'll know if the dealers you're working with are in the right ballpark. Should you try to chop off 1k or 2k more based on the economy? Generally, Edmunds and KBB adjust for that already, and how you want to negotiate for the 1K or so is up to you. Given sales right now, time of the year, etc. the cards are probably in your favor for the better deal.
"Outstanding" Definition: Vehicle is in exceptional mechanical, exterior and interior condition with no visible wear; it requires no reconditioning. Paint will have a glossy appearance. Vehicle has no mechanical and/or cosmetic problems and has a clean engine compartment. Exterior and interior are free of any damage. Tires are in nearly new condition.
"Clean" Definition: Vehicle shows some normal wear but has no major mechanical and/or cosmetic problems. Paint still has a glossy finish and may have slight scratches or dings. Some reconditioning may be needed. Interior will have minimal fading and wear. Tires have substantial tread remaining.