The Marshmallow updates are now rolling out to the Galaxy S6 family as of this time so it is expected that the Galaxy Note 6 shall have it out of the box.
In terms of price, rumors are pretty silent about it. But accordingly, the lack of curvy Edge screen will help keep the cost of the Galaxy Note 6 down. However, since the device is larger than its predecessor, the likelihood that the Galaxy Note 6 will be a little more expensive than the Galaxy Note 5 is quite high.
When the Galaxy Note 5 was launched and released in the US last year, it carried a retail price of $700. When the Galaxy S6 Edge+ was launched in the UK and European markets, it even came out more expensive with a price of £750.
It is most likely that the Galaxy Note 6 will come out in the UK and the European markets with a price range anywhere from £600 to £700, which would actually make it cheaper in price with the Galaxy S6 Edge+ but definitely more expensive than the Galaxy Note 5.
But since Samsung has yet to make an announcement or statement to either confirm or deny these rumored features, specifications, release date, and price for the Galaxy Note 6, it is best to take every information with a pinch of salt.