|1957||Koyou Bussan Co., Ltd. is established.|
|1968||Koyou Bussan starts a rental service for construction sites.|
|1970||Koyou Lease Co., Ltd is established. (Spun off from the Koyou Bussan Rental Department.)|
|1980||A new building of the Koyou Group is constructed in Akasaka, Minato-ku, Tokyo.|
|1989||Data management systems are unified into an office computer.|
|1996||Rental service for real estate sales centers starts.|
|1999||Recycle shop business of office equipment, electric appliances, furniture, etc. starts. (Nationwide expansion of recycle shops “ReSTA”)|
|2000||General rental service for events starts.|
|2003||The introduction of a internal core system completes a nationwide information network.|
|2005||Koyou Logi-X Co., Ltd. is established.
(The logistics department spins off from Koyou Lease.)
|2006||Koyou Innotex Co., Ltd. is established.
(The IT and repair service department spins off from Koyou Lease.) Rental service for corporations starts.
|2007||Rental service for agencies starts.
Facility management service starts.
|2008||ReSTA Co., Ltd. is established.
(The recycle shop department spins off from Koyou Lease.)
|2010||Smart rental system service starts.|
|2013||Rental office and tenant brokerage service starts.|
|2014||ONE Designs Co., Ltd. is established.
(Milan, Koyou Lease (Interior department) and interior business of Work Station are unified.) Koyou Lease increases its capital to 90 million yen.
|2015||Rental service for women working at construction sites starts.|
|2016||The name of Koyou Lease Co., Ltd. is changed to Koyou Rentia Co., Ltd. The head office is moved to Shinbashi, Minato-ku, Tokyo.|