L.L.
I have over $200 invested in GeoTrax...three different very large sets. Unfortunately, one of those sets is the airport.
My children love to play with the other two... combined, the two sets take up most of our living room. I love this train set...the TRAINS, that is. :)
I thought the airport would be so cool...WRONG!!! My children could care less...all the plane does is fly around a little loop. You can't make it go forward or backward like the trains, and it doesn't really "do" anything.
I guess if you already had the train set and she was offering to sell it for 5 bucks, I'd say go for it...but it takes up a lot of space, without the train would be no fun...and $40, used?? I mean, she paid $60 brand new (or less if she got in on sale for Christmas)...seems WAY too high.
Hope that helps!