lionel train set

Okay. It looks like you have a large transformer, a lot of track, and a searchlight car there. I'll start with the track; it's Lionel three rail O-gauge track, meaning it has a width of 1 1/4 inches between the (outside) rails. This track is still widely produced by Lionel, and has a second-hand value of about a dollar per piece, so all the track is likely worth about $20-30.

The transformer is indeed late 1940's-vintage by the look of it. I can't tell much about it from the picture, but it looks like it has a good whistle and reverse-control on it and a good power output. If I could read its letter designation ("model Q 70-watt transformer" or something), I could give you an accurate assessment, but if it's in good working quality a transformer with a wattage of over 45 and whistle control is worth about $40 or so.

The car is a 2420 D.L. & W. wrecking car, produced in 1946 and 1947. Now, it's in pretty good condition except that it's missing one of the toolboxes, which is going to cost it some of its value. This car is somewhat desirable, and even with the toolbox missing is probably worth about $50.

All totaled, I estimate that this lot is probably worth $100-125. You might have trouble selling it for this price, though, because most people aren't looking for track or transformers. I'd split it into two lots, one with the car and the other with the track and transformer, for $50 apiece.