What should I pay for a Mercedes 2018 GLC300 4Matic? (first time buyer)

First time new car buyer here, looking to buy a 2018 Mercedes GLC300 4Matic.The MSRP is 41.5k and I'm adding about 16k of options. The car isn't available in stock so they would have to order it.How much do you think I can bring it below MSRP and what arguments should I bring ? via /r/cars http://ift.tt/2s9s6Ln