First off, I am by no means a Lionel Standard Guage Prewar expert. But I believe you have a true gem on your hands.
The value of a Lionel 318E Mojave set can vary depending on its condition, completeness, and originality. Generally, these sets can range from $1,000 to $5,000 or more at auction, especially if they are in excellent condition with all original parts and documentation.
In addition, to the set you have two freight cars. I have no idea what they are or their value.
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