Partnership

Advantage of this kind of trade - everything is already there: goods, payment methods.
You simply put at yourself to the site a reference, you can write an article. Or place a block with a search form for goods or a block with goods.

In short, all the work has been done for you. And you then what for? You should promote this site, lead buyers.

You should only work with leading sites to which the person has trust, otherwise your ad units will simply be ignored.
For example, the OZON store is the leading Runet store.

This way of income is suitable if you already have a website and we visit it.