Rendering courtesy of Bixby Land Co. – New owner Bixby plans a $10 million renovation and expansion at 9797 Aero Drive in Kearny Mesa.

Rendering courtesy of Bixby Land Co. – New owner Bixby plans a $10 million renovation and expansion at 9797 Aero Drive in Kearny Mesa.

Bixby Land Co. of Irvine has purchased four San Diego office buildings, in deals totaling $21.8 million, with plans for more than $16 million in renovations.

Company officials said Bixby Land plans a $6.5 million renovation of the three-building Mira Mesa Business Park in Sorrento Mesa, which it purchased for $9.3 million; and a $10 million renovation and expansion of a Kearny Mesa building that it acquired for $12.5 million.

Mira Mesa Business Park, totaling 58,701 square feet at Mira Mesa Boulevard and Oberlin Drive, was acquired from 5889 Oberlin Drive Associates, which was represented by Lynn LaChapelle and Bob Prendergast of brokerage company JLL.

Bixby officials said the improvements at the Sorrento Mesa property over the next six months will include new lobbies, elevators, landscaping and signage. Improvements also will include outdoor “living room” amenities, dubbed Bixby Retreat, that the company has developed for its Silicon Valley properties.

The Kearny Mesa property, at 9797 Aero Drive, was sold by Government Props Income Trust, according to CoStar Group and public data.

The seller was represented by Thomas Mercer, Derek Hulse and Ty Moffatt, of brokerage company Colliers International. Bixby plans to expand the current 76,315-square-foot building with 15,783 square feet of new office space, along with outdoor living amenities.

Bixby Land Co. is a privately held real estate investment trust, with a portfolio of office, industrial and related commercial properties totaling approximately $1 billion.