Two way radios are a great idea, might utilize that in the future. I just moved close to a big city, and man was I surprised by the bump up in construction security around here. Back in the small town midwest, any crane you could see had pretty much no eyes on it, sometimes not even a wooden wall around the base. Here, I had to hold my breath and freeze while climbing over a razorwire-topped wall as a guard walked by several feet under me... not exactly what I was used to. Higher risk, but higher reward - looking down on skyscrapers is new to me