I want to buy a R/T ticket CDG-EWR, leaving sept 2nd, but I don't know when I'll be returning yet.
So my plan was to schedule the return for as late as possible (say, january 2009) and just change it when I know on what date I want to travel (and pay the $100 or 200 fee).

A search for this gives me a $1700 fare! Even though a R/T 9/2 to 9/20 is about $700, it goes insanely up if you want to return later.

Does someone know the rules for fares for very long trips? How long do you have to be somewhere for those fares to go up like this, and what's the best thing I can do to solve my problem?

Thanks!