Go with your gut and shop around. I'm not saying this is a bad deal, but you won't know till you compare. And, if you find out later that you missed a better deal, you'll be kicking yourself.
I also would not buy any extras like the outside protection stuff. Save that money and set it aside for other stuff that you will want / need to enhance you camping experience.
I would also verify exactly which brake controller and hitch setup they are going to provide. They may be putting a much higher value on those parts than you could buy them one your own. And they may also be jacking up the prices if they install them in the premise that it takes work to install them. So the $199 brake controller is a $99 part and they make 100 bucks for 15 minutes work.....you get the idea - be careful.