I use Carmel all of the time and LGA is the cheapest with them. A cab from JFK is a flat $45 to any location. Newark (now called "Liberty") is the most expensive by car as the tolls are very high.
LGA is quickest and closest to most locations in Manhattan.
"It's not so much do what you like, as it is that you like what you do." SS
"Time flies like an arrow, fruit flies like a banana." GMarx