1. Previous Communication Reference: Include if there have been prior attempts to resolve the issue, detailing dates and outcomes of previous contacts

2. Legal Rights Reference: Include when you need to reference specific consumer protection laws or regulations that support your case

3. Service History: Include if relevant to establishing your status as a long-term customer or to provide context for the billing dispute

4. Deadline for Response: Include when you want to set a specific timeframe for resolution, especially if the matter is urgent

5. Alternative Resolution Options: Include when suggesting specific alternative solutions or payment arrangements

1. Copy of Disputed Bill: Attach the bill or invoice that contains the overcharge

2. Previous Bills: Copies of previous bills showing normal charging pattern

3. Proof of Payment: If applicable, documentation showing payments made

4. Communication Records: Copies of any previous emails, letters, or notes from phone calls regarding the dispute

5. Supporting Calculations: Detailed breakdown of the correct charges and how you calculated the overcharge amount