Should he mortgage his house to a non-Islamic bank so that he can buy another house?

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Check below answers in case you are looking for other related questions:
Buying a foreclosed house if it is sold at auction because the borrower is not able to pay off the riba-based loan
Should marriage be given priority over settling debts?`

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Related Answers:
Taking a loan in order to buy shares
Paying a debt with a check which the vendor has not yet cashed
Is it permissible to stipulate that the borrower must pay the difference in value if the currency drops?
Buying a foreclosed house if it is sold at auction because the borrower is not able to pay off the riba-based loan
Should marriage be given priority over settling debts?`

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