If I inherit property outside the US, and intend to sell, what are the taxes I will have to pay?

You received a fair market value basis on the date of death in the assets you inherited. Thus, any appreciation from when you inherited to when you sold would be taxed by the U.S. (and possibly by the foreign country - for which you may be able to claim a foreign tax credit). For U.S. tax reporting of the inheritance, see Form 3520, Part IV. You may also need to file Form TD F 90-22.1 (and possibly other forms depending on the types of assets inherited).

Minie:

This assume that you are either a U.S. citizen or a resident alien whose world-wide income is subject to U.S. taxes.

If you are a non-resident alien, then NO U.S. taxes are due.