Using users who are blind or visually impaired to test a website is recommended as a web developer can test there website using blind and visually impaired user and then make changes according to their feedback. Alternatively the web developer could build a prototype of the website and get the blind or partially sighted users to test the prototype. There are a number of things that a web developer must consider when using blind or visually impaired users to test their site.
If it is not possible for blind and visually impaired users to test a site then a web developer could hire the services of a consultant to test a site, however this can be very expensive. Although the cost is often justified as consultants can help to develop the site so that it is accessible, as well as test it. If this method is chosen then a web developer or company needs to ensure that the consultants have access to the appropriate evaluation tools, so that then can test a site for accessibility.