Note 2: Thousands of highly paid employees will cause real estate prices to rise, certainly. But they'll spend on more than just real estate, so the economy as a whole will grow with a lot of incoming money to be spent. As these incoming people are already working for 1 company, their demand for products/services will fall onto the local economy. Which is good for existing residents who participate in that economy. It'll also be good for anyone else who lives (after surviving applicable rent hikes) in the same districts, as the influx of tax money will help local schools, law enforcement, libraries, etc.