1. I would suggest you go with- they try to confuse and add unneeded options.  
2. Dont be afraid to walk at any time- hell, I would suggest you DO walk anyway after a test drive.  they will do their best to keep you-maybe even go lower than expected.
3.Dont let them tell you its the only one around or other BS.
4. You sould not have to pay anything over "dealer invoice" for that car.
5. dont go in there with a specific payment in mind-they can get you any payment over enough time- go knowing how much payments are for your terms.  
6.  dont tell them you have a trade-in till after done- otherwise they will work it to look like they gave you a bunch off, but actually just used your car to do it.
7. dont sign shit until you are actually purchasing the vehicle.   They may want you to sign a sheet with a number they can take ot teh manager-tell them to get the price you want or bye-bye.
8. should be able to get for at least 1-2k lower than MSRP
9. Be an asshole-you already know they are.
10. Walk at ANY time.

Buy a 1-2 year old used car and let some othr sap take the depreciation hit.

You sould not have to pay anything over "dealer invoice" for that car

If you can get invoice that's a good deal, but I wouldn't walk just because you can't.  It depends on the car and the dealer.

Quoted: Buy a 1-2 year old used car and let some othr sap take the depreciation hit.

Or buy Japanese and forget about depreciation!

honda (and acura)
nissan (and infiniti)
toyota (and lexus)
subaru

pick one, buy it, be happy.  make sure the price you agreed upon verbally is the price that's on the contract you sign.