This guy is local to the area and lives and works within a few miles of the dump site(s) -
He sometimes (or use to) work in or near the city- he may have changed jobs or transfered shortly after Melissa's disappearance as he felt there may be some heat. I also feel there was something more personal about Melissa. Perhaps he had a thing for her or knew her aside from her profession.
He is in his late 40's, married and has kids
His wife is "the boss" at home (like most men

She's too good for him and they both know it. She stays with him because it's easier than starting over. She is the primary breadwinner. She has a way of controlling him when he begins to enter a rage. When she's not there to stop it, he becomes dangerous.
She knows he is dangerous but turns a blind eye since he is not abusive to her. He tales his anger toward his wife out on others. Some of the victims may resemble her
People are uncomfortable around him. Although they don't realize why, and most learn to ignore it or file it away.
He has stalking tendencies
He has a gross grandoise delusions.
He may suffer from MPD - people may notice how quickly his demeaner changes or he becomes enraged.
He uses his work as a means to control others. If he is in a power position at work, working beneath him is hell as he seeks out opportunitties to dictate personal lives as well as work life. He may often loses clients (or his job) due to his controlling nature and obsessive and sometimes angry nature.
His work gives him access to the use of numerous vehicles. He uses these vehicles to avoid having any evidence in his own vehicle and for protection in case anyone sees someone picking the girl(s) up
He travels Ocean Parkway often and may find opportunities to bring clients and friends along for a ride on the parkway- (you may wonder why you have gone that route - it's his way of taking a little credit and he may even discuss the case as they drive by the sites)
He may have changed jobs or transfered again shortly after the first of the bodies were found.
He gives clues to those around him. This may be because deep down he wants to be caught because he wants credit for the crimes. Or, it may be that he likes to feel he possess a jhigher intellect and feels he is proving that by dropping clues that nobody seems to catch on to. Someone out there could be putting the clues together
He has revisited the sites and has left clues or trinkets. Look for a meaning to items left at the crosses.
May have recently removed items from the dump sites.
He may have been killing for longer than anyone thinks. Dating back to his late teens or early 20's , either on Long Island or somewhere he went to school or work training. Look for similar style killings in groups of victims (3 or 4) that would have been near his age at the time. He was much younger and able to lure these girls back then.
He is not using the services of these girls prior to the fatal encounters. He would never have sex with an prostitute, He despises them and may have commented about this case or made comments that such women deserve what they got.
He may not be limited to escorts as he evolves once again. He feels there is the potential for entrapment by LE so may not use online ads for victims again. He may look for street level working girls or drug addicts or seek out any vulnerable woman alone at night.
At least one person has thought of him as a potential suspect and he has been looked at by LE already. He may still be on their radar