Retain some control. If you upload photos of yourself, or friends/family with consent, it's worth going for the 'rights managed' licence option – otherwise you'll have little to no control over how your images are used (eg, you could star in an ad for haemorrhoid cream). See Alamy's page on understanding stock image licensing for more on the different types of licences.
Cafe Press: This website allows you to create digital designs that can then be sold on the platform. You'll earn a commission for everything that sells and you'll never have to deal with logistics like printing, warehousing and customer service. If you have some graphic design skills, then this is a great potential source for your web-based income. 
Is this because WP is now blocking outside adds on free accounts? WP recent advised users that ads may appear on free accounts. I saw that WP has a plugin just for Amazon posts, but any plugin requires a business account. In looking at the pay-to-play WP account details, it looks like one has to buy the second level account in order to “monetize your website”.
The one thing to be aware of with WordPress Amazon affiliate plugins is that you don’t want to use one that offers link cloaking. This is a method used to protect affiliates from a threat known as affiliate link hijacking. However, Amazon expressly forbids the cloaking of their links, so you’ll want to avoid plugins that do that or always be sure to disable that functionality if they give you the option.
Take good pictures. Some of the options below don’t require you to actually take the picture and sell the product, but for the ones that do, make sure you take a clear picture that makes your product stand out from the others.  If you’re going to be taking a lot of pictures, set up a small “studio-like” area in your home with a backdrop and proper lighting to really make your pictures come across as professional. And of course, you’ll want a good camera too.
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