In the course of building five successive $1 billion companies, Bradley Jacobs has become accustomed to jockeying for position, whether leading United Rentals to what at the time was the fastest IPO in history or haggling with his dad over whether to use the Jacobs name for a startup garbage hauler. But Jacobs, CEO of Greenwich-based XPO Logistics , was in new territory when he sat down to explore a potential acquisition of a counterpart company in Europe - only to learn the other CEO came to the meeting with every intent of buying him out.