I was able to score a number of "premium"  2 x 4s from a person's remodel project that went sour.  I have about 30 2x4 x 7 and maybe 15 that are 3 to 4 feet long.  I have to pull nails from them and because some were toe-nailed together the ends on some are chewed up.  But they were up for a while and should be dry.  They are generally knot-free and straight.  

I also have a table saw and can rip the 2 x 4s into 1 x 4s (finished dimensions would be 3/4" by 3 1/2").  

Now that I have gotten the fascia added around the layout I am working on getting the support structure for the upper level on the peninsula roughed in.  a 2x3 wall down the center of the peninsula will provide the support framework for the upper level.  As well this wall will let me add shelving under the layout to clean up some of the stuff under the layout – hopefully.

Well, we've got the branchline track laid, and the central division yard is next.  Once the trackwork is operational, we'll be in a position to actually "operate".  To support that, I plan to build two moveable staging yards, HMS North and South, one for "north sub" and one for "south sub".  The north sub must contain four trains, while the south will need tracks for six.  With these modules installed, we'll be able to operate all the anticipated trains, and get a feel for operation of the division yard.  

Installed a safety device on my swing gate entry to prevent trains rolling off the edge of the layout. A switch activates a Tortiose which raises a pin up through the track.