You can't have too many outlets

You can't have too many outlets.

I've changed my ceiling lighting three times, maybe think about track lighting or some 'adjustable' design.

I tend to forget shutting off my train power supplies, maybe your top of the stairs plan is better.

Think real hard about what you want on the walls above the layout, shelves are hard to install after trackwork is done.

Drop ceiling a must

Definitely install a drop ceiling. After years of procrastinating, I finally took advantage at the time of tearing down my old layout and installed a drop ceiling, utilising some of the old benchwork to stand on. Did all the work myself which saved heaps. Used all new steelwork, but factory seconds ceiling tile which looked just like new to me. Also saved money by using second hand troffer lights that were being thrown out of a local bathroom tile showroom because they were upgrading to LED lighting. Great idea, when the budget allows, I hope to do the same LED upgrading.

Actual installation was easier than I thought. Plenty of help out there in the form of YouTube videos. BIG HINT: Leveling was the hardest part. If I were to do it again, I would use a laser level.

Radon

I'd suggest that you have

I'd suggest that you have some kind of emergency lighting.  Also make sure that you can deal with humidity.  For flooring if you opt for something other than paint I'd suggest carpet tiles and use a mixture of colors without a pattern so if you soil one of them you can replace it easily with another without it looking odd.

Take your time on finishing

Take your time on finishing the basement. It's worth stepping back and making sure it is a comfortable and nice space that is easy to clean. Time and money well spent, especially your there for the long term. I would give serious consideration to building a stud wall with insulation and sheetrock over the basement concrete or block or what ever the basement walls are. It will make for a nicer backdrop, a brighter room and will also help keep the dust down.....and will make climate control easier to maintain.  A ceiling, either sheetrock or grid also is huge in keeping dust down.

I agree with Dale and others. Drywall those walls

I agree with Dale and others. Stud wall with sheetrock/drywall is highly recommended. I did that and am very pleased with the result. I followed up with a drop ceiling and 2x2 flat panel LED lights. I not only sealed the floor but installed faux wood vinyl tile plank tiles which are easy to clean.

Here is a link to a series of photos.

http://atlasrescueforum.proboards.com/thread/3737/jims-basement-finishing-layout-progress?page=3

Your basement size is fantastic. I could only afford a home with a 900 sq ft basement and only 550 is suitable for a layout. There is only 2 vents in the basement ducting and in winter's it's not really enough for comfort but so far I hadn't taken any steps other than a sweat shirt. There may be a way to cut in additional vents down the road.

Here is the basement framed in with stud wall - newer built homes have insulation already in in northern Virginia - this home was built in 2005.

Here from the opposite direction, drywall and suspended ceiling in, cement floor sealed and vinyl floor plank tiles going in.

Finished except baseboard.  Blue area is train room proper, cream colored room is wife's den with the walkout doors.  Not a huge basement but I've managed a decent layout plan and the biggest I have ever planned to build.

Agreed,

Drywall, drop ceiling, paint floor.  Paint the walls sky blue.  You may end up hiding them with backdrops, but they're easier to paint now...  Regarding electrical, don't forget to draw up a circuit outline of what you've had installed - the first time you want changes, you'll be glad you did.

Do you like operations?  Will your railroad have a herd of operators from time to time?  Then think about a crew lounge and minimal bathroom(come to think of it, put a 2-piece bath in regardless; add a laundry tub for modelling activities if you have room), near the bottom of the stairs if possible.  If you decide to have a crew lounge (doubles as a family room), can it incorporate an outside view?

Also, don't forget to plan for a modeling space/workroom.  My workspace resides below my (not yet built) staging yards (they're to be 48" and 64" above floor), which is a compromise but will work.

Sounds like you've got retirement plans in this space.  As you get older, you, or others, may develop mobility issues; plan for whatever assistance is reasonable; my stairwell is 42" wide, to better accommodate a chair lift.

As usual, YMMV.  These are just some ideas to think about.

Blair

Another Bit

Check the walls for cracks before you cover them up and seal them. Not a lot of fun to go down to the train room one day and discover that you have a real life river in the basement.

Make sure you put insulation on the walls. It is worth it's weight in gold in the temperature difference it makes.

If you can come up with some photos of the basement you may get some more detailed info/suggestions.

Jack

Ceiling Height?

You don't say what your ceiling height is to the floor joists above.  All the basements I have owned have had the height to the floor joists under 8', some quite a bit under.  Drop ceilings take away some of that space.  For a low ceiling I would either drywall the ceiling or spray paint the joists, ducts, pipes, etc with white paint.

Put in lots of lights.  My basement train room is 17'x44' and has 10 light fixtures in the ceiling - 2 rows of 5. That works, but I could use another 4.

Put in 20 amp circuits for the outlets.  I had one basement where I had too many electric things in one location for 15 amps and had to run an extension cord from an outlet on another circuit.

Have a place for a dehumidifier to sit and continuously drain.

I don't know what your tools are, but try to have a place other than the basement for circular saws, table saws, etc.  They throw a lot dust.

Good luck

Paul

lounge/workbench space

One thing you might not think of is having a separate area where your crew can relax between trains, and/or you can do some of the messy work that you don't want do do on or near the layout (a haze of sawdust or pink styrofoam does not make a good addition to your scenery. If you can get a corner with a window you will have natural light and a place to vent a paint booth.

drainage, drainage, drainage

The most important thing is drainage. You said walk-out, so I'm assuming you still have one wall that's buried to the level of the basement ceiling and two sides that are half-buried. 

North Carolina usually means lots of trees around, and trees mean leaves and pine needles, and that means clogged gutters and drains. The single most important thing you have to do to keep water out of your basement is keep your roof gutters open and the water draining away from the house - preferably more than just a couple feet. In my last house I had a french drain in the driveway that would regularly stop up, and that was even worse - it would turn the driveway into a lake, which if I didn't get out there in the rain and unclog the dang thing, would back up until it was against the house. The only time I had water in the basement was because that happened. 

You can do your best to seal cracks, but keeping the dirt outside your foundations from getting soaked is the more effective way to keep water out of the basement. If you have in-ground sprinklers, make sure they are working right and don't spray against the house. For next-to-the-house flower beds, prefer drip irrigation (and not too much of it). 

And of course make sure yard drainage is sufficient so that you don't get a lake backing up into your walk-out door or garage door.

You might think about

You might think about insulating the floor too, if you have the headroom.

My basement is pretty cool in the winter. I'm refinishing it before starting my new layout, adding insulation behind the exterior walls. I'm also insulating the floor using something called AG flooring underlayment, which is basically a deeply dimpled high density polyethylene (sp?) that acts as a vapor barrier and provides air space that acts as an insulator. On top goes plywood or OSB, then the finished floor. Should help with heat in the summer also. The basement should be really comfortable by the time I'm done.

Be Very Specific About Electrical Requirements

If you opt to have electrical work done (like independent circuits for layout and/or room lights), layout power, room power, and things like which of those circuits would be switched/not switched), be very specific with your asks and verify everything as soon as the work is done.

May sound obvious but  I learned the hard way. While my house was being built I submitted a list of requirements for my train room for isolated circuits and switching requirements but did not find out until a year and a half later (when I actually got started on a layout) that it hadn't been done correctly.

To their credit, when I called the electrician, they pulled my file, examined the requested work and determined that it was their mistake - and fixed it at no charge. But it would have been much easier if it was done right in the first place (and fewer holes in the walls/ceiling) if I had discovered it before the finish work was done.

I didn't have a bathroom in

I didn't have a bathroom in my town house basement and it was a constant annoyance.  This basement had a rough-in for a bathroom so my wife and I finished it as a full bathroom.  Unfortunately the walls were too narrow to put a tub bath in but the shower is the nicest in the house.

A lounge area is a good idea too.  I sacrificed the back room to my wife and it will be a lounge area for her or if there are guests for the train room.

A utility sink is a big plus too.  I had the plumber plumb lines installed a utility sink in the 14x14 foot unfinished HVAC/Water heater room where I also have storage shelves and a workbench.  The sink has been a big help while we were finishing the basement and will be handy for the layout building as well for plaster or other things.

I'm close to finishing my

I'm close to finishing my Basement and working on it again today.  Drop ceiling I think is a must..... I put in plenty of wall plugs....put down some nice tile buy my walkout doors.....I installed on the floor DRI-CORE 2x2 subfloor panels and carpet is being installed over this next week,... And ill put in LED lighting once I make up my mind on what I want to use. Flat screen TV's will be on 2 walls each side of the Basement.  And ill run wires for my surround sound audio system. When all is finished ill start on a Layout?? I Hope.

Lots of good suggestions,

Lots of good suggestions, thanks. I will be taking my time and getting this right, so lots of research and planning still to do. I won't be rushing into the basement work as there is a fair amount of plumbing work to do for the main floor, so I want easy access. After that is finished I'll start on the basement. 

A couple of answers to above replies:

- Radon test was done, it is under EPA standards but at the upper end of safe. I'll probably install a mitigation system anyways just to be safe. I hadn't thought of sealing cracks in the floor, but I will do that.
- Basement is bone dry luckily. There are some improvements to be made with drainage in the yard, but the inside is good. I'll be monitoring it before doing any wall work to be sure.
- Emergency lighting was high on my list - it's pretty dark down there even in daylight
- I already have a dehumidifier with a pump, I plan to either run the line outside or tap it into a waste line.

Hopefully closing Wednesday afternoon, can't wait!