Buying the car in France can save money.  Many sellers will handle the importation process for you (for a fee).

As for petrol vs diesel, first decide if you can handle the ruckus that a diesel makes.  Modern four-cylinder diesels are pretty smooth on the road but they're still obnoxiously loud and harsh at idle.

Wojtek, the reliability indices would like a word with your assertion, that German cars, in general, are better: http://www.reliabilityindex.com/ - see Top 10 Best and worst - and why do you leave out Porsche?

Thanks a lot, guys. These tips are all helpful. @FerneyL, the website is very useful to know the tendency of failures of car models to consider before purchase. But the site is based on the U.K. domestic data so that the cost of repairs and availability of parts are different than those in Germany / CH that would certainly differenciated the popularity of certain makers (like German cars)among consumers depending on the country. The website data indicate the reliablity of Japanese cars better, overall, than German cars anyways, I think... Importing a car from Germany or France may be a good idea for me, too, I am thinking now. Thanks again! I hope more info would come up...

What about car dealers in Geneva anyways? A good one for Japanese cars? Anything one should know?

Because of the dealers annual sales quata, Nov or Dec would be a good timing to buy a new one as they do make a good deal for customers to sell out their cars in stock. Or, waiting until the next Motor Show in March 2013 in Geneva may be another way... What do you think?

Buy a Porsche Boxster (yes, German..) and be done with it. Two seats. Need more? Double up for a 911. Consider a third-generation Mazda MX-5.

Don't forget that as of 1 July 2012, a new CO2 tax is levied on imported vehicles with CO2 > 130 g/km. 

I have a similar question, but slightly simpler.

Are there any reputable used car dealers in Geneva? I want to buy a small cheap car but many of the dealers look very dodgy !!

http://www.autoscout24.ch/

Many thanks to all for all info and advice! Reading all these and looking around, I am now very much interested in Toyota Urban Cruiser 1.33 Luna, perhaps in France...

You can also contact Autociel, they are very helpful especially MARC their manager. www.autociel.ch

do not forget to buy 2 Ethylotests.

Thanks, gerald m, I got them some time ago a couple of days after the day that the French law entered into force. By the way, until November, no one will be fined in France for not having them in the car, but receive only a warning. Penalty fining will start only from November... Getting Ethylotests could still be a tough thing now. When I found them at a pharmacy near my work place, all petrol stateions, pharmacies, Carrefour etc. I visited said, "out of stock", "don't know when they will come in stock.." At the pharmacy I found them, they were free of charge as it still had some free samples for the promotion of non drinking & driving, and its their validity is until 2014, long enough from now. Some pharmacy in Geneva may still have such free Ethylotests, but again, it could still be difficult to find one in stock in any of such places, I think...

Dude... you worry too much. You don't care about the dealer, go for the car you want/right price combination. If the car has all the standard maintenace done on time and some for of warranty you are fine.

Buying from Germany (better market than France, and more attentionate drivers) is worth it for new cars and/or very expensive models, otherwise i wouldn't mind. For a new car you can deduct the VAT, for a used car the VAT is embedded in the price and you pay Swiss VAT + import tax + admin fees on top.

@richardm & catlin (and others for relevant info & advice), thanks a lot!

After all, I may just buy one from a dealer in Geneva/Versoix to avoid seemingly complicated procedures; many numbers (I am not good at "mathmatics":-0); the time that may take long; long distance to the dealer's location when needed to go there again (e.g, insurance/gurantee matters); etc.

Besides, these days, the price of a brand new car in France near Geneva seems not really cheap or cheaper than that of in Geneva/ Swiss romande region. It could make a reall big differece of the price if buying from a dealer far away from Geneva in those countries, but I would not spend too much time and take my head for that. 

I will carry on looking around for a while anyways without any rush...