Lenders outside the United States


I saw the topic not to use lenders outside the United States. I’m wondering why not to use them. I’m not from the US and my lender(s) also. I have a LLC in the US and now I want a contract for my lender(s). For me and the lender(s) It’s (just) an agreement on the ROI (loan) in the LLC and the duration of the investment (loan) I will use the loan for Tax Deed and Lien purchases.
Can anyone give me some advise how to do this the right way? I’m looking for a standard contract that I can use for al the lenders I have from different countries, is that possible?