When reading the news it seems developers, architects, engineers and contractors are fascinated with using unmanned aircraft on their next big project. And legally, any of them can fly a drone for recreational purposes within his or her field of vision and at a height of no more than 400 feet above ground provided they are not in restricted areas like airports or government installations like the White House. But whenever they step into the commercial space, new rules apply; and to avoid large fines here’s some advice.