Central Orange County is seeing a rise in property values, thanks to strong tenant demand and rising rents. The recent sale of City Tower illustrated the upward trend. KBS Strategic Opportunity REIT purchased the 20-story, 435,177-square-foot class-A office building from Torchlight Investors for $147.5 million or $338 per square foot. City Tower is the tallest building in Central Orange County, and is leased to UC Irvine Medical Center, Enterprise Rent-A-Car, Travelers Insurance and York Risk Services Group.