I buy specialist vintage items on ebay and have never had a problem in about 25 transactions. But, being a specialist area, you get to know the good vendors quite quickly and I always read the sellers history of comments before buying. You quickly also get to spot the people who clearly know nothing about the item(s) they are selling. If you are new to ebay, I recommend lurking and watching for a while to get a feel for the area you're interested in before plunging in. Like Wolfgang, I've saved a HUGE amount of money on many quite rare items but have been lucky so far.

RS