If you're thinking the long holiday weekend would be a great time to shop for a new car, here's a tip: Do your homework before heading out. While Black Friday and holiday sales events come with special deals, they can vary greatly among automakers and dealerships. And with cash incentives slowing and zero percent financing offers harder to find, the more legwork you do, the more likely you are to find a good deal. Dealers are typically eager to sell in November to clear current-year models off the lot and help close out the year with the strongest sales possible. And although you might find even lower prices on some 2018 models closer to the end of the year, the selection could be more limited.

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"If you need or want a particular vehicle, the inventory might not be available later in the year, depending on what you're looking for," said Matt Jones, senior consumer advice editor for auto research firm Edmunds. Some automakers have temporarily revived zero percent financing for well-qualified customers — i.e., those with really good credit scores. For instance, General Motors is offering the rate for 72 months (six years) on popular models including the Chevy Silverado 1500 pickup truck. Ford, Hyundai and Nissan also are offering the bottom rate on certain models for limited times. However, such financing deals will likely become fewer and farther between, thanks to rising interest rates. Since late 2016, the Federal Reserve has raised a key rate seven times to prevent the economy from overheating and has signaled that the next hike will come in December. Those increases push the cost of borrowing higher for a variety of consumer loans.

New-car financing Loan element October 2018 October 2017 October 2013 Term 69.12 months 69.19 months 65.66 months Monthly payment $542 $516 $477 Amount financed $31,200 $30,866 $27,605 Interest rate 6.21 percent 4.95 percent 4.19 percent Down payment $4,063 $3,966 $3,652

Just 3.8 percent of autos financed in October came with that rock-bottom rate, according to Edmunds research. That's down from 5.7 percent a year ago and marks the lowest it's been since 2007. Incentive spending by dealers — such as cash-back deals — also are down a bit. J.D. Power estimates October's average was $3,742 per auto, down $143 from $3,885 a year earlier. At the same time, both the average price of a car and the cost to finance it have been rising. In October, new-car buyers paid an average of $32,947 for their new ride. And the interest rate on car loans reached an average of 6.2 percent last month, the highest since January 2009, according to Edmunds.