Need Advice on a 2007 x3 please!

[TorqueMonster]

Hi everyone,

New here and new to the BMW world as well. I have recently had my eye on an 2007 BMW X3 3.0si with executive and m package at a local used car dealer. I've read a lot of the used car reviews on line and am torn on what to do and if I should take a leap of faith and buy this SUV. It's a one owner with only 55k miles which already seemed fishy as BMW never kept the car and sold it to a used car dealer. The car drove fine but I didn't feel the power in the lower gears and has now got me thinking if there are any transmission issues.

What should I be looking for? I did notice some oil around the oil filter but not sure if it was from a recent oil changes or leak. I will be getting it inspected at a local Indy shop but thought if there are common issues to look out for would be helpful before I end up buying something I regret. Anyways to test the transmission while test driving? Any sounds or things that are tell tale signs? Sorry I know that's bit open ended but really looking for guidance and not wanting to loose 15 grand either. The looks to a clean car and service records didn't show much other than some seat issues and oil changes. I'm going for a test drive soon so if anyone can provide some key things to look out for would really appreciate it.

Thanks in advance.