I'm in a similar boat and will bring bringing my cat to the UK in a couple of months. However, the tricky part is that I have a layover in Amsterdam, and am told I'll need to clear customs there as well. I do not live in the US now, and this was really the best flight for our cat, and also enables me to have her fly in cabin for the longest leg of our flight.
Does anyone know if you need different documents to clear customs at the Amsterdam airport? I have tried contacting the ARC in Edinburgh where we will land, as well as the freight agent we'll use in Amsterdam, and even the Amsterdam airport, and it seems no one can give me a straight answer.
Also, what exactly does the ARC do? It sounds like they review documents for free, but then I was given a pet relocation quote of 300 pounds when making an inquiry with them. I was mainly worried about getting my documents checked to avoid any problems, but would hate to pay such a high fee if this is in fact a free service.