Money can't buy you happiness, but when it comes to rental cars, it seems that saving it probably won't bring a smile to your face either.
According to J.D. Power's 2013 North America Rental Car Satisfaction Study released Tuesday, price remains the most commonly cited reason to choose a rental car company—yet those who make their selection based on price are the least satisfied with their experience.
"We asked people how much they paid as an average daily rate for a rental vehicle," said Rick Garlick, global practice lead for the company's hospitality and travel group. "There were two tied at the top—Hertz and Avis with a median of $50 a day, followed by National at $48 and all the way down to Thrifty at $37 a day.
"Despite being one of the highest-priced rental agencies, National is actually at the top of the leaderboard in terms of satisfaction with cost and fees," said Garlick.
Furthermore, that satisfaction helped push National to the top spot in overall satisfaction in this year's survey. Based on six factors—cost and fees, pick-up process, return process, rental car quality, shuttle bus/van and reservation process—the company achieved a score of 809 (on a 1,000-point scale), edging out last year's winner (and corporate sibling) Enterprise at 799.
Even with its relatively high cost, National scored well, says Garlick, by easing the pick-up process through its Emerald Club program, which allows frequent renters to choose any car on the lot that conforms to the class of car they reserved.
"You not only bypass the counter, but you pick the vehicle you want," he said. "If you like a red car or a brown car or you want four doors instead of two, you have that freedom of choice. Of course you're more likely to be satisfied—you picked it."
While bypassing the counter is generally considered a positive—satisfaction with the pick-up process averaged 820 for those who do so vs. 770 for those who stop at the counter—the survey also suggests that a human touch still matters.
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It can be as simple as a smile, says Garlick: "When you're interacting with people who are smiling and positive, your brain actually releases chemicals that make you feel good. It's a straight, linear relationship—the more smiles people get, the higher their levels of satisfaction."
In the current survey, for example, overall satisfaction for customers greeted with a smile from one employee was 58 points higher than for those not greeted with a smile (693 vs. 635, respectively) while satisfaction scores among customers greeted with a smile by four employees was 200 points higher than among those not greeted with a smile (835 vs. 635, respectively.)
"It doesn't take any longer to smile than to be sober and stone-faced," said Garlick. "It's a fairly easy fix."
And one, he says, that promises a better payoff than merely offering a low price: "You have to have a competitive price as a point of entry, but whether it's rental cars or hotels or anything else, people who buy on price tend to be much more critical consumers."
In fact, according to the survey, overall satisfaction was 756 among customers who selected their rental car company based on price compared with 828 for customers who chose a company based on good customer service.
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"It's the perception of you get what you pay for," said Garlick. "If you're renting a vehicle from Rent-A-Wreck, you're not going to be as happy as you'd be if you rented a nicer car even if you paid less money."
—By NBC News contributor Rob Lovitt. Follow him on Twitter.