My wife and I are in the initial planning stages of our second European vacation to be taken in 2014. Last time we went, we flew into Munich and out of Paris, three weeks later. We found that three weeks was about perfect for us then, but may want to stay longer this time, possibly up to six weeks. Our initial itinerary stretches from Amalfi to Edinburgh, with flights into Rome and out of London. However, I am thinking of buying one-way tickets to Rome, and purchasing return tickets in Europe when we are ready to come home. I know that would be more expensive than buying open jaw RT tickets, but would like to have the flexibility of returning when we feel like it, from wherever we happen to be at the time. Do any of you have any suggestions as to how we can best (read "economically") retain flexibility on our return flight ?
The most economical way to do what you suggest is to book open jaw tickets (including the return leg), and either stick to your location and date, or just accept paying the change fee to adjust it. Changing your tickets will probably be cheaper than buying a last-minute ticket from wherever. And a one-way ticket, besides being expensive, might raise questions with immigration about your intentions.
Price two one-way tickets. Then price a round trip ticket, and look carefully at ALL the fees you will incur by changing the return date. Only then can you know which is less expensive. For most airlines, it's going to be the latter method. Even if you get a reasonable one-way fare now, remember that the former method means you are buying a "last minute one way ticket." Since people buying these have few options and the airlines know it, they can charge a fortune. Also, if you can use miles, these tickets are often more flexible (a friend of mine has made multiple changes in mileage tickets, for no or little cost, and he marvels at how much more it would have cost him if he had bought the tickets with money instead of miles).