I was working on the website for the Mandel Group around 2012. At the time, they were transitioning from building mostly condo developments to building nothing but apartment developments. I was told that if a developer builds a 300-unit condo development, you will have folks who buy before the building is completed, but half of those units could be on the market for years. Needing to sit on ~$30mil worth of inventory could keep them from being able to build the next development. If they build apartments instead, they can rent them out right away and start on the next project.