I have a U.S. LLC and a UK limited company and am self-employed and pay taxes in both countries so I'm looking for an accountant (can be in London or in the U.S.) that is familiar with both U.S. and UK tax systems (they do not have to be a qualified CPA or the UK equivalent) and knows what you need to pay to whom, but they:
1. Should charge a reasonable rate and be extremely pragmatic and commercially-minded.
2. Be neither extremely conservative (the type that is a stickler for things that go beyond ethical and legal requirements) nor the hyper aggressive type that wants to run afoul of the law.