Interest refers to the charge for the privilege of borrowing money, typically expressed as an annual percentage rate. It can also refer to a share or a right in a property or in an investment.

Here’s a bit more detail on how interest works in real estate investment:

Mortgage Interest: When you borrow money to buy property, you’ll typically be required to pay interest on the loan. This is the lender’s return on the money they’ve lent you, and it can be fixed or variable depending on the terms of the loan.
Investment Interest: If you’re investing in real estate through a loan or a mortgage, the interest you pay may be considered an expense related to the investment, and thus it could potentially be deductible when calculating taxable income, depending on the laws in your jurisdiction.
Interest in a Property: This term can also refer to having a share or stake in a property or real estate investment. For example, you might have a 50% interest in a property if you own half of it.
Interest Rate Risk: In real estate investment, interest rate fluctuations can impact the value of properties and the cost of financing them. If interest rates rise, the cost of borrowing will increase, which can reduce the profitability of an investment. Conversely, if interest rates fall, borrowing costs decrease, which can make investment more attractive.

In summary, interest is the cost of borrowing money to invest in property, the legal right or share in a property, or the risks associated with fluctuating interest rates. It is a critical concept for real estate investors to understand, as it affects both the costs and potential returns on investment.