I have the typical parasitic battery discharge problem that alot of us X5 owners (2004) seem to have here. If I leave the car sitting for more than 2 days, the battery goes almost dead. I invested in a portable battery which helps, but I've gotta solve this thing. The Stealer wants over $100 to diagnose, but I think I've found a better way. On this Youtube video, the guy shows you how to use a standard volt meter inside your fuse box to find the bad device that's been taking up power when your car is off. You don't have to be an electrical engineer to do it; you just look for a high # when you touch both sides of the fuse with the probes.

Here's the video:

Automotive Repair: Locating Battery Drain Using Voltage Drop - YouTube

From another post on here by jdudjak, the potential problem parts might be:

61356923954 Rain Sensor
64116923204 Blower motor resistor (also called final stage unit)
61356961141 Light control Module

Costs go up as you go down the list. The Blower motor resistor is an easy fix and about $70 from the parts places like FCP.

I'm hoping it's not the light control module, which appears to be upwards of $400.

Anyhow, hope this helps someone.

If I could sell it, I would.