Buying a smartphone in US

Hi,

I am from Germany and for an internship in Michigan. I was thinking of buying a Galaxy Note 4 here. My questions are:

• Where can I hand it in Germany in if there is an error with the device? (assumed I bought it from Amazon or a store)


• Can I set the language to German?


• Will there be any (SIM) Locks or can I put every sim card in (German ones)?


• Would you do it?


• Where would you buy it? American Amazon or a store or somewhere else?