Yeah I wish Costco would actually tell you Costco pricing, you just get whatever the dealer tells you Costco pricing is.
If it were as easy as saying "name your best price" then everybody would say that. There's a lot of back and forth, bullshitting and such. Haggling is a difficult thing to get used to, but in exchange for your discomfort you can save more money.
Going in person will make you look more serious, but then you will yourself be more committed emotionally and more likely to accept a less than stellar deal. If you go in person, be ready to walk out when they don't give you the price you want.
Also, Costco pricing can be +250 miles away. Called a few days ago from StL and learned that the closest Costco dealer was in KC... wtf?????