房产现金流计算器公式

## Property Cash Flow Analysis

Cash flow is the money remaining after all property expenses are paid from rental income. Positive cash flow means the property pays for itself and generates a profit.

### Formula

**Monthly Cash Flow = Effective Rental Income - Total Monthly Expenses**

Where:
- Effective Rental Income = Gross Rent x (1 - Vacancy Rate)
- Total Expenses = Mortgage + Taxes + Insurance + Maintenance + Management

### Why Cash Flow Matters

- Positive cash flow protects against unexpected expenses
- Negative cash flow means you subsidize the property each month
- Most investors target at least $100-$200 per unit per month
- Cash flow does not include equity buildup or appreciation, which are separate returns

计算示例

A rental property earns $2,800/month with 5% vacancy, $1,400 mortgage, $250 taxes, $120 insurance, $200 maintenance, and no management fee.

  1. Effective monthly income: $2,800 x (1 - 0.05) = $2,660
  2. Total expenses: $1,400 + $250 + $120 + $200 + $0 = $1,970
  3. Monthly cash flow: $2,660 - $1,970 = $690
  4. Annual cash flow: $690 x 12 = $8,280
  5. Expense ratio: $1,970 / $2,660 = 74.1%