Mr Farmer said buying the site was a good move from the point of view of the property side of the business.
"But it also made sense from the company point of view," he said. "It's a logical natural extension of our showrooms and allows us to really increase our used car presence."
Nissan will move to a new showroom on the old Domett site, allowing Farmer Autovillage to reconfigure the showrooms for its other brands. The company's dealerships also include Audi Chrysler, Dodge, Hyundai, Jeep, Skoda, Subaru and Volkswagen.
Mr Farmer said the key benefit for customers was that the company would now be able to display used and new vehicles for each make together. Currently, the Nissan used cars shared space in the Subaru Chrysler Jeep showroom.
"We have a strong range of used vehicles from $3,000 upwards but, at the moment, we don't have them in a logical layout," he said.
"We don't feel we're providing the buying public with the most accessible selection."
Once the reconfiguration is completed by the middle of next year, each dealership would have space for its used car selection out in front of the relevant new cars.
"We want to ensure that buyers have the best opportunity to find what they want and to deal with the experts in the brand."
However, Mr Farmer said new car sales were exceptionally strong at the moment, with buyers opting for new over used vehicles because of advantages such as the warranty cover, and the better safety record of new cars.
Farmer Motor Group founder Peter Farmer said the company accounted for almost half the volume of new cars in Tauranga.
"But the big focus of this extension will be to increase our used car capacity."
Farmer Motor Group
• Formed in 1991 by Peter Farmer as Bay Nissan and now run by Mike Farmer, Peter's son.
• In 2008, the company moved into the Farmer Autovillage on Hewletts Rd, with multiple brands in separate showrooms on one site.