To avoid having your hub considered as overly promotional, you should only have a maximum of 2 links to any one domain. If you have Amazon or eBay capsules in your hub, you should have 50 words of text for every Amazon or eBay product that you have. Your hub shouldn't have too many links and any links you have should be related to whatever your hub is about.
Refer to the HubPages learning center guide on hub moderation for more detailed information. Here's the link: https://hubpageshelp.com/standards/Learning-Center... .