Is it Possible to find a decent violin at an auction?

[matesic]

While penning this I was preempted by kyproset who must have been listening to my mumbles. I'd only substitute "amateur" for"professional" and say that I don't have the knowledge or acumen to be a dealer and have never bought an instrument motivated by the possibility of eventual profit

[Ben Hebbert]

Henry, 

Having worked in one of the big-name auction houses, if you ask the specialists ahead of time they will have a better idea of the safe violins to go for in your price range than if you look yourself, and then it's up to you to take a punt at your own risk. If you are lucky, you may be able to take the instrument out for a day, but that is certainly not guaranteed, especially at the lower level and depending on the time before the auction, and if it's a firm favourite within your budget, there is a really strong chance that other people will have spotted it, and all your efforts will be for nothing when it gets bid out of your price range - (or that it becomes less of a bargain when you end up in a bidding war). So if you want to potter around and make it a part of your life to go try and beat the dealer, you may be waiting a long time. If you buy something too easily, you might not have quite the bargain you imagined. I've seen some absolute horror stories in which no one was at fault except the hubris or naïvety of the buyer. People are always happy to talk about the person they know who got an absolute bargain, but for obvious reasons, people aren't so public about the things that turned out poorly for them. 

Everything in auction is fair and transparent as long as you understand that the  first rule of auction is caveat emptor - buyer beware - i.e. it's on you, mate.