New to the forum! Thought I'd share what I have. Growing up my grandfather passed a 2343 Sante Fe set to the family which we ran (and abused ) as kids during Xmas. Other than that, I've not really been involved with the hobby until recently. Well, as life goes, my grandfather's collection eventually passed to my dad and it sat for ~20 years, and I've since ended up with it (haven't exactly inherited - my dad is still alive and kickin' as well as ever ). I'm a tinkerer by nature and have been really getting into the hobby.
All told there are ~300 pieces post war pieces with a good portion NIB, including some interesting pieces - 1950 issue 773, a couple of 2340s, a number of late '40s steamers (726, 2025 which are probably my favorite given their detail and quality, esp. the wheels). All told there are 50-60 locomotives and what must be at least 100 of the 6464 box cars. There are also quite a few accessories - water tower, beacon, coal ramp thingy, etc.
I think my favorite is the military set on the inner track. It was NIB - the original rubber band is still on the satellite car. I had to replace a broken bulb and fix the locomotive missile launcher. It was plainly built as a cheap kid's set (pretty much all plastic) but it's pretty neat given as I understand the rarity of NIB condition (including all boxes and accessories).
I'm still working on a plan to get all pieces somehow displayed. This 5' x 9' layout is as large as I can fit, so only a sliver of the collection can be displayed at any one time. I'll probably go with some sort of shelving. I've had some stuff fixed and restored, and still have a long way to go in getting everything out and serviced, so it'll be a while before I can get it all properly ready to display.
I find it pretty amazing that 90% of what I've unboxed thus far runs fine with zero servicing, and this including NIB and stuff that hasn't run since the '50s.