New to bmw, help, advices please

Hi! I'm new to the forum and fairly new to the foreign car scene, specially bimmers. Just a little background on myself before I go on to the important stuff. I'm 18 now, when I was 16 I got my first car, a 01 ford focus. When I turned 17 I upgraded to a 2003 3.0 v6 6spd audi a4. And now, turning 18, I have upgraded again to a 1998 740il with around 155k. I bought it because my audi was breaking to much, and the 740 was an easy cash buy from my brother. The only thing is that it's quite beat up, and I just don't really like it because of the interior/exterior colors and etc.
so I searched online for another 740 and I found one that, to me, seems pretty nice. Can anyone help me with this? Just to make sure that, really, it is a good move to try in buy this car...
I found a 2001 740i, it has the screen inside and everything.
Here's more details on it,
Mileage: 161,822
Engine: 8 Cyl. 4.4L
Transmission: Automatic
Body: 4 Dr Sedan
Color: Jet Black
VIN: WBAGG83411DN85735
Stock Number: N85735

They are asking $7,750 for it. I was gonna see of I could give my 740 as a trade in..
What do you guys think of all this informations given?
Any advice, comment, suggestion would be great! And thnk you!

http://ps.getauto.com/dealer/details...GG83411DN85735_a_

ANY 13-year-old BMW is a potential money pit, with 7-Series cars being the biggest offenders. Unless you`re an accomplished DIYer with a pretty fat bankroll, I would have to advise you to look elsewhere (unless you want to remain piss-poor for the rest of your life )

If you *are* determined to buy one of these, at least have a thorough PPI performed by someplace intimately familiar with BMWs.

Happy Hunting !

Hey thanks man! That really opens up my eyes. I don't think I'm gonna buy the 01 bimmer anymore. I'll just stick to the one I have now till I can get something newer. Thanks for the help!!