I've been wanting to start managing a portion of my investments on my own, kind of for fun / a challenge, and was wondering about your experience with different online trading companies such as TDAmeritrad, E*trade, etc. Thanks in advance

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2006 BMW X5 4.8is Lemans Blue/Beige/Dark Maple
-Nav, Comfort Seats, Heated Steering Wheel,
Rear Airbags, AUX Input
2009 BMW M3 Space Grey/Black/Carbon
-all options