Advise - Looking at buying an older BMW

[Salty_Dog]

Ok, the idea has come into my mind to buy a Champagne Car for a Lemonade price.

And possibly signing up to UBER with it.

Cars i think are great value are:

2002 BMW 320i E46 Auto MY02
and/or
2002 BMW 735i E65 Auto

I have found a few that look mint with lowish k's
The 320i has 150,000k's for $9000 AUD
The 735i has 100,000k's for $18000 AUD

But, at 2002, these cars are getting long in the tooth.
Hence the price vs luxury balance.

Any advise on looking down this road?
I already have a 2006 X5 3.0d, so i am familiar with some of the BMW things.
I'd like a 7 series in diesel, but i couldn't find any in Australia

Thank You