Good news – you don't necessarily need a fully custom app! Here's the approach using standard Odoo Community:

**The key is your Chart of Accounts Account Types.**

Odoo Community's P&L report at Accounting → Reporting → Profit & Loss organizes accounts by their Account Type. To get the standard format (Revenue → COGS → Gross Profit → Other Income → Expenses → Net Profit):

• Go to Accounting → Configuration → Chart of Accounts
• 2. Make sure your accounts use the correct Account Types:
•    Sales revenue: Type = "Income"

   Cost of goods sold: Type = "Cost of Revenue" (this is key for the Gross Profit line)

•    Other income: Type = "Other Income"

   Operating expenses: Type = "Expenses"

3. The P&L report will then automatically show a Gross Profit subtotal between Revenue and Other Income.

**If the 'Cost of Revenue' type is not visible:** Enable developer mode (Settings → Activate Developer Mode) and it will appear in the account type dropdown.

This gives you the standard P&L structure natively without any third-party module. If you need further custom groupings or subtotals beyond what account types provide, that would require a custom module – feel free to reach out at custom@trewac.com