Nissan Motor Co.’s Leaf electric car has been a big seller for Atlanta car dealer Pat Hoban over the past three years, thanks to its low monthly lease price. But as those car leases are beginning to expire amid cheap gasoline, the vehicle is becoming a bit of a headache.

Mr. Hoban expects between 100 and 150 of the leased vehicles to be returned to his Capitol City Nissan dealership on a monthly basis over the next two years as their leases expire. The problem: used Leafs aren’t attracting much demand.

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