Pflueger Cadillac, Hummer, GMC and Buick will open Tuesday. It will be the company's third new car showroom. The other two are an Acura showroom on Beretania Street and a Honda dealership on Ala Moana.

"This is obviously a big boost for our business," said company President Alan Pflueger. "It will increase our business by possibly 30 to 40 percent."

Pflueger signed a 20-year lease on the Schuman facility on Beretania. The site will be remodeled and redesigned this fall, he said. Transaction details were not disclosed.

Pflueger plans to hire 90 people to staff the dealership. When Schuman closed its doors in November after 111 years in business, 117 workers lost their jobs.

Pflueger also plans to break ground on a new Acura dealership in Kahului, Maui, this fall.

The company prevailed over eight other dealerships that were interested in snagging GM, he said. The automaker looked at dealership experience and customer satisfaction scores.

Pflueger takes over at a time when GM has some hot brands in the market and Hawai'i car dealers are enjoying a revival.

"Cadillac is totally reborn and Hummers are in short supply across the country," Pflueger said. Car sales "are fabulous in Hawai'i. For us, Honda and Acura sales have gone up 20 percent in each of the last two years."

Pflueger also owns three used car dealerships — in Waipahu, 'Aiea and downtown Honolulu.