Los suministros, la construcción y el montaje, también forman parte de las obligaciones del Contratista. Incluso en la definición más restrictiva de un contrato llave en mano, el contratista es dueño de la construcción de la instalación completa lista para ser operada. Sin embargo, es habitual que el cliente exija al contratista, la contratación de subcontratistas determinados. De esta manera, el cliente trata de asegurarse la calidad de ciertos componentes o negociar directamente el precio con ciertos subcontratistas.
While these models have diminished in mature e-commerce and online advertising markets they are still prevalent in some more nascent industries. China is one example where Affiliate Marketing does not overtly resemble the same model in the West. With many affiliates being paid a flat "Cost Per Day" with some networks offering Cost Per Click or CPM.
Since the emergence of affiliate marketing, there has been little control over affiliate activity. Unscrupulous affiliates have used spam, false advertising, forced clicks (to get tracking cookies set on users' computers), adware, and other methods to drive traffic to their sponsors. Although many affiliate programs have terms of service that contain rules against spam, this marketing method has historically proven to attract abuse from spammers.
En principio, es responsabilidad del Contratista la elaboración del diseño del proyecto y que éste asegure la instalación para el cumplimiento de las garantías de rendimiento requeridas contractualmente. Si hubiera que tener en cuenta las obligaciones de diseño de forma independiente a las de construcción de la planta, la naturaleza de estas obligaciones y la cuestión de si se han cumplido adecuadamente, sería un aspecto independiente de la calidad y el rendimiento de la planta finalmente construida.

In 2008 the state of New York passed a law asserting sales tax jurisdiction over Amazon.com sales to New York residents. New York was aware of Amazon affiliates operating within the state. In Quill Corp. v. North Dakota, the US Supreme Court ruled that the presence of independent sales representatives may allow a state to require sales tax collections. New York determined that affiliates are such independent sales representatives. The New York law became known as "Amazon's law" and was quickly emulated by other states[44]. While that was the first time states successfully addressed the internet tax gap, since 2018 states have been free to assert sales tax jurisdiction over sales to their residents regardless of the presence of retailer affiliates[45].

Spam is the biggest threat to organic search engines, whose goal is to provide quality search results for keywords or phrases entered by their users. Google's PageRank algorithm update ("BigDaddy") in February 2006—the final stage of Google's major update ("Jagger") that began in mid-summer 2005—specifically targeted spamdexing with great success. This update thus enabled Google to remove a large amount of mostly computer-generated duplicate content from its index.[33]