Can you figure out airline costs these days? Looking at the endless price and schedule lists, it’s like shopping at Sid the Sharpster’s used car lot. Caveat emptor, for sure!

For instance, while recently trying to book from New York’s JFK or Newark’s EWR nonstop to LAX in Los Angeles, there were great differences in prices. Depending on the day and time you fly, the cheapest coach round trip price ranged from $239 to $699.

On the other end of the scale, the more expensive seats were from $1,807 to $3,558. We realize that no matter where you sit, all passengers arrive at the destination at exactly the same time. Of course, the wealthier flyers get bigger seats, free booze, dinner and other benefits. But, is it worth another thousand bucks or more to eat a just-unfrozen steak TV dinner and sip champagne in comfy, tilt-back seats?

Best prices are for the midweek red eye flights, those scheduled from about 9 pm and later. A non-stop cross-country takes about four hours, so it can’t be too uncomfortable in cheap coach seats. International flights are another story. On bargain lines, such as Virgin Atlantic, on certain special deals, you can take the red-eye from JFK to London for as little as $350 each way.

It requires spending eight hours cooped up in a five-across coach seat squeezed in like a canned sardine. Passengers just a compartment away pay $2,500 or more each way for a seat that tilts back to become an uncomfortably bent bed.

As a general rule, night owls who don’t mind flying red-eye get the best prices on airline tickets. For a next flight, check first with your favorite online agencies. Also, especially for last-minute deals, it’s worthwhile to contact the airline’s website directly.

Whatever your plans on flying, whether day or night, short hops or overseas, do your homework. Be flexible about schedules, and keep a bag packed in case you grab a last-minute bargain. Unless, of course, you prefer shelling out thousands extra for that bottle of cheap champagne and microwaved steak dinner.