It isn't hard to do if that is what you are worried about. Use an OE filter, refill it, warm it up to check the level

One of the reasons it is so expensive is the liability, if the new fluid causes a problem. It isn't due to the complexity of the fluid change

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2007 X3 3.0si, 6 MT, Premium, White

Retired:
2008 535i, 6 MT, M Sport, Premium, Space Grey
2003 X5 3.0 Steptronic, Premium, Titanium Silver
2002 325xi 5 MT, Steel Grey
2004 Z4 3.0 Premium, Sport, SMG, Maldives Blue