Interstate Oil Inc. the 186,494-square-foot office building located at 601-649 Broadway in heart of Downtown San Diego. The building was built in 1927 and renovated by Home Federal Bank in 1983. The 14-story building was purchased for approximately $20.5 million, nearly $110 per square foot. Two tenants occupy nearly half of the building: the County of San Diego and On Broadway Events Center. Ben Tashakorian of Marcus & Millichap represented both the buyer and the seller, Broadway JDS Inc.