Some thoughts from somebody who has a bit of experience buying and selling collectible guitars...

I'll concentrate first on electric instruments, as acoustic instruments are often subject to a completely different set of criteria.

The first thing to be aware of is that folks selling vintage instruments are generally doing it for a reason. Commonly this is to make money. Often it is (also) because they don't really care for the instrument. If they did, they wouldn't sell it for any amount of money in the world. This is something you need to guard against, because you might soon find that you don't care for it either.

Now examine your own motives for buying such an instrument. Are you buying it to play music? Or are you likewise buying it as an investment - to make money? The answer to this question can greatly affect your purchase.

If you are buying the instrument to play, you need to evaluate the sound and playability - and placing lower priority on looks and finish blemishes.

If buying for eventual resale, looks and finish are everything. Especially take note of any cracking (as opposed to finish checking, which is normal for an aged instrument).

A common mis perception is that older instruments sound better than newer ones. There is some truth to this, as time affects the bonding of the lacquer finish with the underlying wood; which affects the instrument tone. On electric instruments, this turns out not to have a great deal of importance, since tone can be synthesized and enhanced electronically. It is also argued that vintage pickups sound better than new ones. This is entirely bogus. While vintage pickups in a vintage instrument might have some value, if you're after sound, there are pickups available today which have gone through years of evolution and sound better in almost all cases than older designs. 

The brand name and model is extremely important for resale, however here you are falling prey to speculative bubbles, which could collapse at any time. A lot of '68 Strats and older Les Pauls are on the market, and could be termed speculative. Supply and demand is what ultimately affects price. One of the most collectible guitars of all time is the original '50s Flying V - of which less than a hundred were ever made. These sell for whatever the market will bear. Any modern V, Les Paul, or Strat - are commodity items. Beware the bubble. It can bite.

The guitars which ultimately are sought by collectors are those that were quality instruments, but which failed in the marketplace and hence have limited supply.  There are lots of modern day analogs to the Flying V - and you can generally pick these up for a pittance; hold on to them, and eventually sell for large sums as they vanish from the marketplace.

If you're buying an older instrument to play, ignore the pressure to buy completely. Only buy the item if you decide that it has the sound and playability your style of music requires. If it doesn't - pass it by. There are usually lots more out there to choose from in the same price range. Keep playing them until you find the right one.

Don't ever buy a vintage instrument sight unseen or through mail order.

For acoustic instruments, Martins usually do well in the marketplace. But here, the sound and playability are much more important than for electric instruments. If an instrument sounds like cardboard, it isn't worth the cardboard it's made from. In the acoustic category, you'll find the most impact of the natural bonding of wood and lacquer which makes for a prized sound. Usually the sound improves ('mellows') over the first ten years of life, stabilises for about twenty years, and then things start to fall apart, literally. A hundred year old guitar doesn't necessarily sound great - but can be a valued investment as a museum piece. You probably wouldn't buy one to play professionally as the fragility also increases with age. Finding replacement tuners for a 50 year old instrument can be a challenge, and will detract from the value if you replace any of them. The gears are often soft brass, and don't hold up well over time. 

Rolling Stone magazine released its 1000th issue today.

Which reminds me, I've got a copy of issue 68 - October 13, 1970. This is the memorial to Jimi Hendrix edition following his death in London.

If this has interest to you, $50 and it's all yours.  The pages are a bit yellowed, but what do you expect from a 36 year old newspaper? (in 1970 Rolling Stone was loose-leaf and resembled a newspaper more than a magazine.) 

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