It depends on whether they can show me some of their previous work, usually in the form of pictures from past projects. Serious vendors even invite prospective clients to their stores where they will have a "demo room" showcasing their work.
If they have neither, then it's absolutely fair to ask them to do a small audition project first. Otherwise how can you be sure they're competent?
Keep in mind this idea doesn't exist just in recruitment. It's basically recruitment's version of what's called a "proof of concept", which is proof that the party that is pitching/asserting something (i.e. their skill) can actually deliver.
In my past of applying for jobs as a designer, I had companies that would ask for take home tests. I always refused and of course didn't get the job. Conversely, other companies I worked for offered freelance positions (probation) before settling onto full time which I thought was far more effective and fair method at evaluating me as a long term candidate.
If they have neither, then it's absolutely fair to ask them to do a small audition project first. Otherwise how can you be sure they're competent?
Keep in mind this idea doesn't exist just in recruitment. It's basically recruitment's version of what's called a "proof of concept", which is proof that the party that is pitching/asserting something (i.e. their skill) can actually deliver.