Is American power of attorney valid in a different country to sell property?

It is possible. But I would think that you might need to at least have your POA "authenticated" by the Russian consulate, before it would be accepted, there. I have used that process with other countries. You can also check with a Russian attorney to see what they allow. James Frederick

Regardless of whether the NJ POA could be used to sell property in Russia, it shouldn't. Since Russian land transfer officals are highly unlikely to be familiar with NJ POA law [not to mention English legal language], the cost to answer your question as to a particular U.S. document probably would be very high. It likely would be much cheaper to consult a Russian lawyer, use documents prepared by that lawyer, and just appoint POA through a Russian typical document.

You need to contact the nearest Russion Consulate. If Russian authorities accept a US Power Of Attorney, it is very likely you will need the PAO to be notarized, stamped with the The Hague Apostille by NJ State Authorities and translated to Russian by a translator that is certificated by the Russian Consulate/Authorities.