Hi folks, 
I am the guy, who had kept the BMW 530i in the link above for a number of years. It's a marvelous piece of engineering, even if its more than 10 years old. For those of you, not having any experience of German cars, you will certainly be blown away by the luxury, performance, looks and little quirks.
Even though I have sold it and moved on, I still believe there is no better car than a BMW 5'er for a driver, if you can afford to maintain it. If I get another chance, I will go ahead and buy a 5'er one more time.
I had purchased this car in a fairly good condition with some issues, which had been known at the time of sale. I also had a very competent BMW technician with full set of tools on my side. This guy had worked and trained other technicians at BMW dealership AGMC in Dubai for over 13 years. So I was confident of undertaking any job at factory spec. The part availability is not an issue in Saudi Arabia, we can get all original and OEM parts easily in the market.
By nature, the BMWs are a very sophisticated machine, and require high maintenance at regular intervals. The high performance comes with a lot of TLC. I always poured Mobil 1 Long Life 10-40W Fully Synthetic Oil (takes 7 liters) every 10,000kms religiously. I checked for any oil or water leakages too every week religiously. This is how much you have to care for it. But then, I did drive it a lot. My average mileage per month had been very high, but mostly on highways. It was also fuel thirsty due to my heavy foot. 
I am not aware of parts availability scene or mechanics in Pakistan, so you have to do your own research on it. And you will need a trusty mechanic. At 100,000+ kms, this car will require a lot of maintenance.
I had owned my car for 5+ years, and during that time, I had undertaken complete engine rebuilt (due to the previous owner probably not using good engine oil and not changing oil at shorter intervals), complete transmission teardown and rebuilt (due to water and transmission oil mixing in the transmission), in addition to certain smaller breakdowns of coolant system etc.
I spent a big fortune on the car, and didn't feel it, as I loved every minute driving it Alhamdullilah.
