So average retail on a 2018 is $4700. If you are getting the bike alone for roughly that price, then you are ahead of the game. If your out the door price is tax, tags, title and whatever, then you should be just about right. Some people on here got crazy cheap deals on their bikes, some people got screwed. All that matters is if you think it's a good deal. If you like it, then it's a great deal and you should buy that bike and ride the snot out of it.
TLDR; life is short, buy the bike.