In a nutshell it's as simple as this - Don't Buy an Asian "Restoration!"

Rather than trying to rehash what has been said a thousand times before we will defer to these websites:
http://www.scooterlounge.com/Vespa/Asian/Asian.shtml
http://www.rovers-usa.com/forum/viewtopic.php?t=1938
http://www.thevespawizard.com.au/the_black_vbb.htm
http://www.scooterlounge.com/Vespa/Asian/Asian2.shtml
http://www.scootart.com/Asia/1/index.html
http://scoot.net/faq/Asian_Restorations
http://thekneeslider.com/archives/2006/09/15/vietnamese-scooter-restoration-update/
http://www.vespacedargrove.com/Vietnam/
http://tinyurl.com/6l7pdo
http://www.scoot-central.com
http://wattayaknow.com/scooterrats/vbcreview.htm
http://www.madaanmotorsthief.com/
The Sites Below Are Known to Sell Asian and Indian "Restoration" Scooters. This list is by no means complete and there are too many eBay and Craig's List scammers to mention.
http://sundarscoots.co.uk
http://vespaxporter.com/eng/
http://www.1wants1.com/
http://www.allvespa.com
http://www.carpediemclassicscooters.co.uk
http://www.classic-vespas.com
http://www.classicalwheels.com
http://www.dreamscooter.net
http://www.goldenscoots.com
http://www.goodtech.biz/vespas/scooter-range-02.htm
http://www.groupharrington.com/classic
http://www.italianvespa.com
http://www.ktscooters.com
http://www.lambretta-scooter.co.uk
http://www.mahaa-scooters.com
http://www.modscooters.com
http://www.powderscooter.com
http://www.retrovespa.com
http://www.scooterati.co.uk
http://www.scooteraz.com
http://www.scooterlegends.com
http://www.scootersofseattle.com/scooters.htm
http://www.vespa-scooter.net
http://www.vespaclassics.com
http://www.vespaking.com
http://www.vespavietnam.com
http://www.vivovespa.co.uk