1. When you report your US income and expenses, the house will be included. No need to file anything special. You will file a Sch E for a rental house on your tax return - if you own it as an individual. If you have formed another tax entity, like a partnership, then it will file the rental house and pass through income and loss to you on a K-1.
2. In order to deduct mortgage interest, the loan must be secured by the house. Therefore, the paperwork for the loan should include the house as collateral. If you make payments in a foreign currency, convert it to USD for each date a payment is made.
3. Be sure there is no issue in the Tax Treaties. It would be unusual.
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