Buy/sell items

Instead of adding another forum, maybe just send an email to the seller or post on his thread..."Is this 2R, 3R, DCC, etc.?"

A little work on your part can keep you from making a buying mistake.

Also, I've not posted topics in many moons, ago, so how does one reply to a topic or a buy/sell item?

Sure.  There's the OST, MTJ, RRLine and a host of Yahoo groups available that you should know about - several even specific to narrow gauge and even On3; several specific to traction as well.  Takes a few minutes to locate some of these, too...