Train tickets purchased at the last minute tend to be at full price. To get an idea, login www.sncf.com and assume a trip next week between Paris and Amsterdam. Then look at the price if you order the ticket at the beginning of October. You might or might not see a significant difference. The best prices are ordered three months in advance.

The order of your travel will be determined by your flight to the Middle East. If you find a low cost flight from any of the continental cities you mention, use that as your end point and work backwards from there.

If you are referencing this Sept/Oct, you are rather late in being able to find the lowest train fares. Buying any transportation ticket on the day of travel will almost always mean you will pay the highest fare available. You can look here for fares:

www.tgv-europe.com (select Afghanistan or Antarctica as your country to preclude being sent to Rail Europe and higher prices)

Additionally, this period is the very busiest of the year for Parisian hotels and the most sought after hotels will have long ago been booked. Attempt any Paris hotel search for this period and you might be surprised at how much is not available.

No train tickets, or especially plane tickets, purchased on the spot are going to be anything but the highest price available, assuming you are talking about this upcoming September/October. You have already forfeited any bargains.

Same for hotels. If this trip is for 2012, you have effectively done yourself out of any savings/bargains at all.

I would absolutely not add any destinations. Four in 2 weeks is already a jam.

I would go from London to Paris to Amsterdam to Berlin and fly to the Middle East from there, unless prices for flights to the Middle East dictate otherwise.

This wasn't the best plan if you were trying to save money.

They are adequate if that is what you want to see. They wouldn't be my choice, but they are yours.

I would purchase ticket for the Eurostar right now,, they would have been cheaper two months ago, but as it is you have to hurry .. Then purchase tickets on Thalys for Amsterdam. Not sure about Berlin , would not be my personal choice.

As noted, its so late, you will have to work hard to find good accomadation at a good price in Paris,, September is a very busy month!

well, I think train fares in Europe are generally "reasonable" in any case, even when regular fare. I think a lot of train travel is a real bargain in Europe, it is always cheaper than in the US for the same distance, seems to me. Long distance TGV fares (in France, for example) can be a bit pricey, but still aren't that bad for the distance covered. Short distance regular trains it doesn't usually make any difference when you buy them.

However, there really isn't much choice given the itinerary isn't even set yet.

I'd do UK, France, Netherlands, Germany, but the reverse would make as much sense.

You certainly must know that air fares are never the same price on day of departure as bought 3 wks or more in advance.