As millennials shop for wheels they're finding it's not as easy as swiping right on their smartphone. Some dealers might assume millennials don't have enough money and show them little respect. To avoid common car-buying headaches, experts offer these five tips:

Use

technology

E-mailing a dealer's internet department — which operates separately from the traditional showroom sales force — can quickly get you a firm price quote and a less confrontational buying experience. Or try texting. Many dealerships have created text and live chat lines for answering questions about inventory and, sometimes, negotiating.

Get preapproved for a car loan

While dealerships typically have access to the lowest interest rates, it's still essential, particularly for millennials, to shop for a car loan before going to the lot. Getting preapproval sets a baseline, so that you know what interest rate you deserve when you are at the dealership.

Drive multiple cars

Millennials tend to skip the test drive, turned off by interacting with pushy salespeople. But it's important to drive multiple cars to compare features and make the best choice. Set up back-to-back test-drive appointments for your top picks through the internet department, preferably during the slower weekdays. The differences between competing models will quickly become apparent.

Avoid test-drive hassles

Some salespeople might refuse to let millennials test-drive a car, or first demand a credit check to make sure they have enough money. With a preapproved loan, the shopper can simply say he or she is a "cash buyer." Asking to see a shopper's driver's license is legitimate, but make sure you get it back right away so they can't hold you hostage.

Keep the deal clean

To sign the sales contract, a customer is escorted into a dealership's finance office. There, the finance manager tries to build more profit in the deal by selling extended warranties, alarms and other extras. Decide ahead of time what you want and what you are willing to pay for it. If all else fails, let your feet speak for you. Be prepared to walk away.

NerdWallet