Return on Investment (ROI) is the ratio of total return to investment amount, showing investment efficiency. Real estate investment considers both rental income and value appreciation. Generally, an annual rate of 5% or higher is considered a good investment.

Cash flow refers to the actual cash inflow/outflow after subtracting all expenses from all income. Positive cash flow allows continuous investment maintenance, while negative cash flow means additional funding is required.

Cap rate is the ratio of net operating income to the market value of the property. This indicator shows the profitability of the property itself without considering loans, making it useful for comparing with other properties or investment products.