There is no need to make the simple, complex.
As MF1 has pointed out, when you die, you will owe these people money. The estate will have to repay the debts of the estate before distributing the money to the beneficiaries.
You should have a formal loan agreement in writing stating the conditions under which the loans are to be repaid. This should also state the interest rate to be paid.
If you are not paying interest on the loan, you could be subject to Gift Tax(Capital Acquisitions Tax). If the lenders get interest, they will have to pay income tax on it.
If you are giving them some share of the increase in value of the property on disposal, then I am not sure about the tax implications.
To protect the interests of the lenders further, you could execute a mortgage in their favour. You would need a solicitor to do this for you. This means that they "own" the property until the loan is repaid. Your executor would not be able to sell the property without first agreeing to repay the mortgage. (In general, we use the word "mortgage" to mean a loan, but I think that the legal meaning is more precise - it refers to the security for the loan.)
I see no advantage in life insurance unless you want the overseas property not to be sold.
Brendan