This question's come up recently: http://www.easyexpat.com/forums/viewtopic.php?t=14265

As you're being paid from your US office you need to check with your company accountant what your tax situation will be. German taxes are rather steep (50%-ish including healthcare) so if you can avoid those and keep with the more wallet-friendly American taxes, you'll be happier.

1. Maybe. If you're in the German tax system, single and don't have too many vices, you'll be OK. If you're in the American tax system, you'll be as comfortable in Frankfurt as you are in the US. Apart from rent, costs of living aren't huge.

2. How long is a piece of string? I stayed in a student dive for €300/month (shared bathroom and kitchen with other students. I over-paid because of how close to the centre it was). My parents stay in a rather comfortable flat for about €1200/month. There are infinite variations in between, so work out how much you're prepared to pay and see what you'll get for that. Rent will be your biggest cost if you go it alone - don't be afraid to rent someone's spare room or group together with colleagues if there's more of you going.

3. See above.

4. They are more expensive than in the US, but not enough to justify trying to bring supplies over with you. The only thing you should bring from the US is aspirin. In Germany it costs about €5 for a box of 12 tablets.

5. If you rent an apartment to yourself, no, you'll pay electricity and water. They're not massively expensive - allow €50 to €70 per month to cover it.

6. Frankfurt has some grotty-looking areas but is basically safe. There are many districts to Frankfurt - look at all of them. I lived right next to the Sachsenhausen bar district, and the only risk there was to my liver.

7. Transport - use public transport and get a zone 5000 month pass for €50-ish (2003 price): gets you onto all public transport, all the time, for the whole of Frankfurt. Entertainment - Frankfurt is awash with good places to eat, drink and make merry, things to see and do. If you get a German bank account, remember that it costs about €10/month to keep it open.