>>2963161A pristine M3 is probably worth more than a pristine M6 just because the M3 is older. But the M3 was also the most manufactured Leica, if I'm not mistaken, and slightly beaten up but totally functional ones are probably one of the cheapest Leica options besides special snowflake stuff like the CL or Bessas.
I bought this M3 for like $550 from KEH plus the lens for like $500, it had a couple of dents and scratches but it worked perfectly. The viewfinder was clean and crisp and the shutter was accurate, no problems. Then I used it for a year or so, got tired of rangefinders, and sold it back on ebay for almost exactly the same prices. Between fees and shipping charges and stuff the camera probably ended up costing me less than $100 which is easily less than what my DSLR depreciates in a year.
PS Leicas aren't that great. They're great cameras and all but there's a reason they became a toy for rich people once SLRs came out. Don't be a retard and get a rebranded Panasonic, that's stupid. At least an M3 is a legend and is the camera that actually got Leica its reputation.