To qualify for a Netherlands work permit, the candidate should be a professional and have the skill set and qualifications necessary to fill a position that has already been unsuccessfully advertised in the Netherlands, or which is subject to recognised shortages. There is a legal requirement that the candidate is between 18 and 45 years of age, although it is unlikely that a candidate under the age of 23 would have the relevant experience or skills necessary to fill a professional position.
If the you are a non-Netherlands company supplying services to a Netherlands based client, then the candidate should usually have been employed by you outside the Netherlands for at least six months.
NB: A Netherlands work permit is employer-specific. If a candidate has a permit to work for one company, and they want to work for another Netherlands company, this would not be possible – unless/until the new company has obtained another work permit in their name.