What is the ruling on partnership in real estate construction, where money is paid to be refunded after one year with an estimated profit margin, while taking a bank check as collateral for the principal amount paid? And is it permissible to recover only the principal if the transaction is not Sharia-compliant?

The operative principle in contracts is based on intentions and meanings, not on mere words and structures. What transpired between you is a loan with interest, which is an invalid contract. You are obligated to take back only your principal capital without any increase, as Allah Almighty says: ﴿And if you repent, you may have your principal – [thus] you do no wrong, nor are you wronged.﴾ The Prophet, peace and blessings be upon him, cursed the one who consumes usury, the one who feeds it, its scribe, and its two witnesses.