Oops, I calculated the price using the peak rates for the train. The price per person roundtrip should instead be about $11.00.

David, that was so nice of you to take the time to figure all that out. People on the Philly site are awesome. I have seen some really nasty remarks on other forums, especially Florida. You have all been so helpful. I am getting excited about my trip now that I have done my homework and you have all contributed and validated some of my thinking. Thank you all and I am still eager to listen to any ideas.