Hiring the wrong person to manage your AdWords campaigns could cost you money and with very little return. Save yourself from the trouble and do a little research and evaluation first.
You have two options: do the job yourself (manage your own AdWords campaigns), or hire somebody else.
Most companies opt to hire someone from outside the company, as it can be difficult to hire someone specifically for PPC management. As the job requires both high level technical and linguistics skills it takes around six months to train someone to a satisfactory level, or, an experienced PPC person can cost your company a hefty salary.