I would suggest:
breadcrumbs
title
category
image
+ now I would add:
seller name (location) - phone number (reveal + call tag directly)
+ description and so on...
The phone user (in fact all the users) have no time and no will to "discover" where are hidden in the page the seller info.
Therefore, usually, on desktop they look on the right of the image and on the phone quick after the title + image. (I think that it is better to add the basic seller info after the photo as usually, in most cases, the photo is the main element that make people buy a product.
In any case, the related items should be AFTER the all add block elements (image, description, seller information, comment)
Hope it helps.
PS: If other have other ideas please post here as only this way we will have the best product!
PS2: the same on the detail page on desktop: on the right block, think that the seller block + phone number should be BEFORE the location.
Anyway, once i will buy it I will change it myself as, according to many studies, the internet users are likely to click or access pages that are similar and they are not willing to learn new things. (aka: the left top of the page should be filled with the website logo, bottom with the footer with contact and copyright, the menu AFTER the logo and so on)