Not quite. An item tagged as Prime does not mean it is fulfilled by Amazon. It just means the Prime policies apply. So a reseller can ship it free to you and receive it in under 2 days, free returns etc. But you might not get the instant credit (when scanned at the shipper) like you do with Amazon fulfilled items.
Prime - Sold by Amazon - Fulfilled by Amazon
Prime - Sold by Reseller - Fulfilled by Amazon
Prime - Sold by Reseller - Fulfilled by Reseller
Non Prime - Sold by Reseller - Fulfilled by Reseller
The last case can still be free or paid ship.
You might get different customer service if you are signed up for Prime. You will get different customer service on the 4 cases above.
I don’t hold anything against Amazon on ship times during the epidemic. But generally they have still been good.
I do wish they would tell you which carrier they will use before ordering.
I thought I replied to this already, but I mentioned Amazon.ca
To use the proper terms it is Fulfilled by Amazon (FBA) or Fulfilled by Merchant (FBM) on Amazon.ca FBA is prim and handled by Amazon, FBM is neither prime nor handled by Amazon.
I think you broke up the order type too much as 1, 2 would be the same, 3 I have never seen in all my years buying and selling, and 4 is a regular marketplace sale backed by an A-to-Z guarantee.
1, amazon obviously handles everything to do with the purchase and can refund you without a need to return (soooo much stuff thanks to that, even expensive tablets)
2. amazon will still provide some customer service but at a little more limited in giving things away free, but still do.
3 & 4 you deal with seller first (well you can talk to amazon about it but that is the wrong way to go about it), if there is an issue still then the A to Z guarantee kicks in.
For informing you of the carrier before hand, that is just a logistics nightmare but you will know moments after and can cancel if you have a problem.
Reminds me, I better cancel two Mavic Air 2 orders right now.