won't start sometimes. possibly ignition switch or key problem

[VR777]

Hello,
Past few months I have problems starting the car... Once a while, when I turn key to start position (cranking) nothing happens. Usually it starts after 2nd try. Sometimes if I hold long enough, it will start to crank. Today it started from 9th try (was ok whole day after that). When I say nothing happens, I really mean it. No dimming lights, no clicks, nothing. I think it may be relative to Ignition Switch or dying battery in key. Could someone, please, help me with an advice? Dealer will just throw different parts in car and rip money off
thanks in advance
BMW X5 2006, 70k miles