Hi, I am going to be selling a residential apartment property in another country and it has been held for over 15 yrs.

Hi,
I am going to be selling a residential apartment investment property in another country and it has been held for over 15 yrs. There are two scenarios:
1. I would pay taxes on the capital gains in that foreign country with which USA has double tax treaty, so I should get credit for the taxes paid there. In this case I would have to declare the capital gains and  would have to pay the long term capital gains tax (for Federal return) and adjust for the difference based on taxes paid in the foreign country. How would the state tax be calculated for North Carolina? Would I get credit for the taxes paid in the foreign country? Would the taxes be base don a preferential rate since this is a long term gain?
2. I may choose to invest in some specific bonds in that foreign country and that would make my gains tax free as per the tax laws there. How would the gains be treated in USA?

Thanks,
RG