Again, don't believe everything you see on tv. "Hitmen" are usually tweakers looking for their next fix. The suave, debonair, master-of-disguise and kung-fu ninjas only live in the minds of Hollywood screenwriters.
Most murders for higher are done for a few thousand dollars, which makes it even more pathetic, I suppose.
Yes, I agree with your observation-he was a hired killer.
Very true, with the possible exception of certain contract murders of the very wealthy, famous and or well known mobsters, that were killed by professional killers.
My hunch in this case is Mr. Smith was involved, as someone who loaned the gun to a former prison associate, or was given the gun by an acquaintance after the victim was murdered...
Something led the investigators to Smith...That information seems to have been very credible, indicating they're on the right track.