You can take a bus and then transfer to the subway to port authority bus terminal in Manhattan.The bus fare is $ 2.75 per person with free transfer to subway. It takes longer than driving, perhaps 2 hours. Look up the time on Google Maps day of travel. At Port Authority Bus Terminal you can get the shuttle to Stewart. People have been reporting that costs $20 at this time. Most people in NYC who dont drive, take this shuttle. We are usually using Stewart for the cheap fares.
Renting a car might honestly be cheaper. You can drop it there. That's generally a bad idea. You are gonna lose any cost savings on the taxi
If your flying in today, forget it. Norwegian is cancelled today because,of the max 8 aircraft's. Otherwise you can uber or lyft from lga to stewart
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