I feel like I’ve been to US consulates and embassies to get new entry visas a hundred times. In reality it is probably 5 times. Still too often! I’ve only lived in the US since 4.5 years, but I have had many short contracts and a new contract always means I get a new visa, and a new visa means I need a new entry visa. I was on a J1 for 3.5 years and am now on my second H1B.
In London, there is a photo booth in the embassy, so no need to spend money and time beforehand to get pictures taken. Make sure to bring money (not sure anymore if coins are needed or bills are OK). I had my appointment on a Monday morning and got an email that I could pick up my passport from a spot in central London on Thursday. The US embassy in London is quite large and you can buy something to eat and drink inside.
In Amsterdam, however, there is no photo booth, so you need to bring pictures. I brought pictures, but the background wasn’t white enough (sigh…) so I had to go and get new pictures taken. There is a place on the Roelof Hart Plein, called Foto Amsterdam (Roelof Hartstraat 4), that makes pictures for 12.50 Euros. A friendly local makes and prints pictures for US visa quickly. His shop opens at 9AM (but today, he was late and I had to wait until 9:15). Last time, I had my appointment on Monday and got my passport back by mail on Friday. This week is Christmas, I had my appointment on Tuesday the 24th of December and got my pasport back by mail on Thursday the 1st of January.
Being A Better Scientist 