David Martini is a private investigator.
He works in the private sector for whoever can afford his not-inexpensive fees but few who do fork over the sizeable amount are seldom unhappy with the results, at least according to his reputation. But investigator is what many others call him.
If asked, and he is occasionally, Martini prefers to say he is a negotiator. He is someone you would call to represent you in bargaining when being there in person is not advisable. Often replace that last work with prudent or with safe.
In his either late 30s or early 40s (he mostly shrugs if the subject comes up), he really enjoys his work and the many places it takes him and the many interesting people he meets. Except those who decide he or his client or both need to die. Those he does not care for that much and unfortunately for Martini, there are a few of them around.
Martini was not always an investigator or negotiator. He started out as a lawyer and apparently he was not bad at that either but sitting in an office behind a desk was not what he wanted to do so after a time he gave it up, or so he indicates. More likely occasional work from being a lawyer forced him to travel and the transition slowly took place. He is clearly happier.
Though by no means a super-man, Martini can nevertheless take care of himself in a fight which is good because he gets into a lot of them. He can handle a gun without shaking but knows when to duck if called for. He is good looking enough to catch a lovely lady's eye and wise enough to wonder if she is a bit too willing too fast.
Lastly, Martini is a sharp operator who trades barbs with the best of them and generally has fun, not letting anyone browbeat him or push him around. And being quite intelligent, when someone tries to sneak one past him, Martini will let the person know he is on to him. And he will do so politely.