Watch out for the standards of Amazon 3rd party sellers... If you'd trust the company ordering directly, great - it's just the same ordering through Amazon (many smaller, but reputable camera stores put things, especially hot-selling items and odd used gear that may not have a local market, on Amazon to increase exposure). Oddly, a D850 (several months ago, when you couldn't get one) and a Linhof Technikardan are both more likely to wind up on Amazon from a good local camera store than an everyday item like a D750 or a 5D mkIV.
The problem comes if you wouldn't trust the seller directly - the fraudulent New York camera dealers of the 80s and 90s who got swept out of business by the rise of B&H and Adorama have all popped back up on Amazon (and eBay). I'm not sure whether or not it's the same people running them, but their old tricks are in full force. You can find gear marked up well above retail, poorly marked gray-market imports, camera bodies missing batteries, chargers and the like...
What's wrong with the following line? "Nikon D850 and 24-70mm f2.8 lens - $3999"? Sounds like a great deal, no? Well, nothing specifies that the 24-70mm is a Nikkor, let alone any particular Nikkor. This was an old trick from Cambridge Camera Exchange...
You can bet that lens is the cheapest 24-70mm f2.8 they could find. If you're lucky, it's a Tamron or Tokina AF lens, quite possibly a previous generation, in a Nikon mount. If they're really feeling evil, it's an old manual-focus Cosina lens or something, in whatever mount they can find. I'm not sure if there are any left new in boxes, but those guys used to love to dump Yashica/Contax mount lenses and screw-mount lenses that way...