A partnership involving Boston and Hawaii real estate investment firms has bought the OHANA Waikiki West Hotel with plans to turn the 659-room budget hotel on Kuhio Avenue into an upscale property.

Boston-based Rockpoint Group and local firm BlackSand Capital along with California-based management firm Evolution Hospitality announced the purchase Friday.

A price was not disclosed.

The seller was Queen Emma Land Co., an affiliate of The Queen’s Health Systems.

The buyers said they plan to give the hotel at 2330 Kuhio Ave. its first "comprehensive renovation" since the 18-story building opened in 1970. Work is slated to begin in the spring and be done in phases.

Planned upgrades include modernizing all guest rooms, renovating the lobby and pool area, and adding a full-service restaurant and lounge.

Outrigger Hotels Hawaii, which has managed the hotel since the early 1970s, will continue in its role at least temporarily. Any transition of management will be determined once renovation plans are finalized, the buyers said.

Outrigger had owned the hotel on land leased from Queen Emma Land. The ground lease expired in 2010, and Queen Emma Land assumed ownership. Outrigger was interested only in being a partner, but not a sole investor, in buying the hotel with a new ground lease.

The new owner entered into a long-term ground lease, the terms of which were not disclosed.

Rockpoint was founded in 2003 and has invested roughly $9 billion since then, including the 2006 purchase of Hualalai Resort on Hawaii island with Michael Dell’s MSD Capital LP.

BlackSand Capital is a local firm that includes local developers Koba­ya­shi Group and The MacNaughton Group.

Evolution Hospitality was created in 2011 in a move separating the ownership and management of the family-owned Tarsadia Hotels chain.