A four year old lease return BMW is the best way to pick one up. Thanks to fairly high residuals, there is a good supply of returned cars, and they're widely available. A $30K 330i with 75K km's is a hulluva car with some warranty left, and years and years of great driving left.
I still think the best buys are the last of the 328 E36's, as there are still 1999 Coupes available, and they are CHEAP. The E36 was really well sorted out at the end of it's life, the 2.8L engine is sweet, and the coupe is still handsome. For less than a new base Civic, the E36 is a sweet deal.
But, the E46's prices are dropping quick too. The 99/00 sedans are in the market, and competition can be high, creating the occasional buyers market for these cars. While some might prefer the E46 for it's current look, the build quality of the final run of E36's was very high and if you find a well cared for example, they are awesome cars.
I would look at the comparables in your home market and price it at the top of them. Punch up the ad with "lots of extras" and "mint condition" (if true) and see of someone bites. But, if every other ad is $22K, forget $28K. Dealers are GREAT for bumping used prices, allowing you to price in their neighbourhood, at top of retail.
Now, if your car shows poorly, forget it. Make sure the interior looks BRAND NEW. Wax it, polish it. Clean every nook and cranny on the wheels. Fix any minor flaws. Pop for a new windscreen. Odds are that most are pitted, and your car will seem much nicer thanks to it's super-clear windscreen. The car will feel new.
Have the service history laid out and organized. If there is warranty remaining, get blanks of any warranty transfer forms to help the new owner. Make sure the manual and all the related books are available with the car. CLEAN the glovebox and storage compartments RIGHT OUT. No crap at all.
If someone questions your high price, explain that your car is well cared for, immaculate, and then prove it.