We’re big fans of Slack. Before Slack, we used Skype, Google Hangouts, text and email. Slack has been a much better system for internal communication between our different groups that doesn’t burden our inboxes. The only con we’ve experienced is integration issues with Google Hangouts.
We recommend DevSpark for offshore development. They do what is called near-shoring. You get access to a non-US workforce, which helps you keep costs down. But they’re based in Argentina, so they’re in the same time zone. They have people working locally to manage what is happening, which is great. And they do projects and development at very reasonable costs.
We rely on Truman James for finding real estate brokers. They work with companies to place them in coworking spaces, find their own space, or even sublet their own space.