1. Previous Communication Reference: Include when there have been prior attempts to resolve the issue, summarizing previous correspondence

2. Legal Action Warning: Include when you want to indicate intention to pursue legal action if the demand is not met

3. Return of Goods Details: Include when physical goods need to be returned as part of the refund process

4. Third Party Involvement: Include when relevant third parties (such as credit card companies or consumer protection agencies) have been or will be involved

5. Damages or Additional Costs: Include when claiming additional costs beyond the original purchase price

1. Proof of Purchase: Copies of receipts, invoices, or order confirmations

2. Product Documentation: Photos, descriptions, or documentation of defective products or unsatisfactory services

3. Communication Records: Copies of relevant previous emails, letters, or chat logs regarding the issue

4. Warranty Information: Copies of warranty cards, terms of service, or guarantee documents

5. Expert Reports: If applicable, any third-party assessments or expert opinions regarding defective products or services