Reply when a customer wants to supply their own materials

A customer wants to supply their own materials. Help me reply.

The job: [details]
What they want to supply: [e.g. tiles, parts]
What usually goes wrong: [e.g. wrong quantity, damaged stock]
How I'd like to handle it: [e.g. fine, but no guarantee on the materials]

Ask me up to 3 short questions first if anything important is missing. Wait for my answers.

Then:
1. My terms in plain words: quantities, checking on delivery, guarantee on my work versus their materials, delays.
2. A friendly reply to the customer.
3. A line to add to my quotes for next time.
4. A checklist for the day the materials arrive.

Use only what I've given you, leave blanks for any price or fact I haven't given, and don't invent anything. UK English. Not legal advice.

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