Brands that have the least depreciation

I think VAC & VTL should be included as well...!!

I agree about McIntosh.... maybe not for everyone but sure holds its value.  I bought a 5 year old C15 preamp locally for $700.... enjoyed it for 5 years and sold it on eBay for $1350...   

Classic  gear like Marantz, Mac and ARC.  Try buying a pair of Marantz Model Nine amps, or a Model 7 pre-amp.  Big bucks for sure. Take a look at what an ARC SP-3 goes for these days.

If we would have been smart enough to invest in, and stock pile these early editions back in the late 70's and early 80's, it would have been akin to collecting collector cars.  

Frank