Need insight on how how online auction SEO works for big sites (1 m+ pages)
I need some insight on how online auction SEO works for big sites which has 1 million+ pages and how they get indexed in Google. If anyone with some expertise on this could shed some light on this subject i would be thankful. I have a few questions:
1. How does Google index product pages on an online auction site where products come and go quickly. How can you index the right product pages that are being put up and not the old ones that are expired? Which is the best way to do this?
2. I read that it could be a advantage or even a must to implement rich snippets or schema. Is it beneficial to implement this to an online auction site and how can you do this in the best way?
3. How does the CMS automation work for such big e-store with 1 million + pages work? What can or should be automated?
4. Should e-stores with 1 million+ products be optimized for images?
I hope someone could assist me with these questions