Sections of the highway are damaged, with broken drainage covers.
114 applications were received for the 104 apartments that were being sold off-the-plan.
The facility will house banks, exhibition halls, food outlets and venues for lectures.
The provisional budget for the project has been set at Sh4 billion.
The office block adopts green architecture.
Donald Trump, who has golf resorts around the world, is among 43 other interested parties.
The investors are required to complete the project over a maximum of six years.
The road is inspired by the N1 highway that runs from Cape Town to Harare.
The homes, costing Sh1m for a two-bedroom unit, will be built on 1,000 acres in Athi River.
Construction of the Tazara Flyover commenced in 2016 and was completed in 29 months.
Talks are underway for China to fund a new highway and rail extension.
The Chinese-funded Orpower 22 power plant will take 17 months to complete.
Bedsitters will rent for Sh3,200 per month on a 30-year rent-to-own plan.