For transition era you would need some articulated steamers to run from the tipples to the yard where the trains going to either a port or a major customer were made up.  In the early 1950s C&O used H-4s and 6s as mine run locos and H-8s to move out of the mountains.  Then the train would have a K-3 or K-4 on the point.  If you really want to be authentic, don't forget the mine head house and the company town!  Coal dealers would be serviced by a local, not a unit train.  C&O and N&W used unit coal trains way back to the '40s,  probably earlier, and the other coal haulers probably did the same. 

For logging, you need smaller locos - Mantua has a nice articulate, both with a tender and as a tank loco.  Logging needs log cars. Check the Walther's catalog for ideas. 
Gene

Pricey and be careful, but Hawthorne Village has several Christmas trains in On30. 
Gene

Thanks.  I have never heard of Dr. Ben's.   I will check into them. 

The company houses are the City Classic two story ones - so plastic. 
Gene

I'm about to do some weathering of coal tipples and coal field company houses.  I can not find my India ink.  What about a wash using weathered or oily black - say a 1:6 or so ratio? 
Gene

Let's face it.  It's impossible to model a steam locomotive in all its versions.  Bachmann chose to produce the USRA heavy Moutain for N&W in its "as delivered" condition and the C&O version "as shopped."  I don't know why they did that, but they did.  BLI did the USRA heavy Mikado for Milwaukee Road "as delivered."  I'd like the 1950s version...
Gene.

Have him check these replies.  For this group to be in such complete agreement is an event worth noting.
Gene

Whatever you do, don't get the Atlas under table switch machines.  Even the Atlas tech doesn't like them!
Gene

nail polish.  BTW, that's a PRR K4, not a C&O K4.
Gene

wa de sg, k
Well, no, I'm not really waiting for a reply. 
The first problem you have is we have no idea what your friend wants to do.  But let's just say he wants to do C&O steam in the late '40s, early 50s.  Great:  Bachmann!  He can get a J-3, a K-4, an H-5, and soon an H-6.  But no switcher!  For that, he needs to go to Proto 2000 for either an 0-8-0 or an SW-9.  And what if he wants an H-8?  Rivarossi is the only choice.  A caboose or two?  You may find something close at Athearn/MDC or at Walthers, but not Bachmann, I don't think.  What about those long coal trains?  Bachmann has maybe two hoppers for C&O.  To get numbers and variety, Accurail is the way to go - but what about all those great Atlas two bays?  And let's not forget the Athearn/MDC six packs. 
If you want to change the parameter to BNSF and 2009 I think you will find the same problem.  I don't think any car/locomotive company has a EOT or FRED device to hang on your last car so that kids can't wave at the conductor....
And then comes the time when you want to add scenery to the layout..... A person with a 4x8 layout set out west might be able to afford all Bachmann trees - but finding Bachmann buildings now is a challenge, and they don't have much variety. 
Gene

I have three of the C&O H-5s - one of which I have not yet run.  The two that have, run fine.  As noted, the original Bachmann 2-6-6-2 is the USRA light Mallet.  The one coming out is the C&O H-4 (6) - not the same locomotive - but very close. 
I agree with Sheldon - it might well be a decoder problem.  Can you try it on DC? If it still doesn't run well, send it back.
Gene

Try many of the DPM or Mainstreet (?) kits.  Use any one that has large show windows so people can see the interior.  Don't forget you will need to put a light inside to see the interior.  Make a viewblock/back wall behind the figures. 
As to figures, maybe War Between the States or Wild West figures would be best - much more popular than War of 1812. 
Gene

A couple of things to remember, though you will find this as you do a bit of research.  As a general rule, a steam locomotive is unique to a specific railroad or system.  Yes, there are the Harrimans and the USRAs, but these are the exceptions.  A NYC Mikado doesn't look like a C&O Mikado, for instance.  Next, just because two locomotives are in the same class, doesn't mean they are identical.  As they got shopped various things got changed:  side mounted air pump (s) got moved to the pilot deck or the smoke box, the loco got a new tender, the bell got moved, a feedwater heater got added, etc.
Another point is that a wheel arrangement had one or more specific names, so saying "2-8-2 Mikado" is redundant.  All Mikes were 2-8-2s.  Some arrangements had more than one name, but there was the "standard" name (Berkshire for the 2-8-4) and the "oddball" name (C&O's Kanawha for their 2-8-4s). 
Gene 

Hey, Sheldon,
I'm reminded of my time in Korea when Koreans would sneak out into artillery impact areas and collect shell fragments after we fired.  At night they'd put blue filters on flashlights and go out while we fired.  Blue is not as good as red, but better than pure white to keep the beam from being seen. 
Going to another country is an eye opener, believe me. 
Gene

You have already posted this question under General, which is where it belongs.
Gene