Edited October 18, 2019
at 03:51 PM
I know GoPro is always offering trade in deals, but I could not find a post on here about their current "$100 off a Hero 8 Black with the trade in of any old GoPro", or any digital camera period (so long as was originally worth over $100). This puts the price at $299 before tax, with free 2 day shipping. Says they will ship prior to the October 15th release.
For questions about what you can trade in:
This can be combined with the current Amex offer to get 6000 points or $60 back for spending $300, which effectively gets the price down to around $240 before tax, ymmv. Shipping is free. Do note that if you're not paying tax, you will need to add a filler item to hit the $300 mark, such as a filter for diving or a lanyard, etc.
They are also offering $50 off the Hero 7 Silver or Hero 7 Black, but keep in mind the Silver does not have a replaceable battery and the underwater case only goes to 40M (recreational diving limit).
I'm not recommending you upgrade or whether it is worth it; I wanted to upgrade an old Hero 4 Silver so I could use my Hero 7 Black batteries. The Hero 8 Black batteries are backwards compatible with the Hero 7 Black batteries, although they claim if you use the 7 Black batteries in the 8, you will be locked out of the highest bit rate options.