Preliminary terms of a development agreement for a project to convert a downtown office building to market-rate apartments was approved by the Des Moines City Council this week. Last fall, Ruan Inc. announced it was forming a joint venture with Block Real Estate Services and Foutch Brothers, both located in the Kansas City, Mo., area, to redevelop Two Ruan Center at 601 Locust St. The 14-story building, which is mostly vacant, would be converted to 221 apartment units, under the preliminary agreement. Commercial uses would remain on the skywalk level of the building. The project would receive up to $5.57 million in financial aid from the city. Developers are pursuing state and federal historic tax credits to help pay for the $81.2 million project, according to information provided to the council. Construction would begin at the end of 2024 and be completed by 2026.