About the only way to get into narcotics/explosives detection is working for an agency that will send you through a handler program and pair you with a dog. Put in 2 years on the street and you will be eligible for contract work as an experienced handler.
In order to be certified to train with narcotics, you need a DEA permit. Explosives require an ATF permit. There is a lot that goes into receiving these permits.
There are also handler certifications you must get before you can work. Narc teams have to be 97% accurate, bomb teams 100%.
It's not an easy field to get into, but once you pay your dues, you can do just about whatever you want as long as you are prepared to travel a lot. Overseas contracting in war zones pays a substantial salary.
When a dog saves the life of a man, it becomes clear that partnership knows no bounds.
Fama - T.E.D.D. OEF XI-XII (GSD)(RIP)
Marshall - T.E.D.D. OEF XII-XIII (Lab)(SF EDD)
Lucian - Med Alert / Mobility SD (Cane Corso)
Pud - the old man (Pit x Lab)
Hank - DW Dog (Cane Corso)