Right now, used Leica prices are on the rise in the US, mainly due to the continued erosion of the US Dollar - not changes in supply nor demand.

Leica prices, like most collectibles, are cyclical. Right now on an upward trend... Like other "investments" you should buy the best quality of scarcer issues if you hope to have any return... Having said that, its hard to believe any of the more common Leica bodies will ever gain that much more in value... The IIIg is interesting example to follow....probably the 'best' modern SM Leica body to invest in...this camera used to sell for $ 1500+ back in the mid to late 90's.... now it sells for $ 750-1000 all day long....

Dan

See the chart below. Last 6 months of the US dollar versus the other major currencies...