Suzanne,
Keystoned Ed is correct these are premium passenger cars and designed for serious scale modelers. Although Lionel is a 3 rail manufacturer, these were a special limited edition, Lionel Smithsonian, and produced for 2 rail scale by a well-known scale hi-end manufacturer. Consequently, they demand a premium price. The last time I noticed the cars for sale they were in the $400-500 price range per car, so don't settle for selling the set for a few hundred dollars. What you have is extremely premium, unique, and quite rare.