Price a job so you actually make money on it

Help me price a job so I make a proper profit on it.

The job: [describe it]
Time it'll take: [hours or days, for me and anyone helping]
Materials and parts: [list with costs, or leave blanks]
Travel: [miles or time]
Other costs for this job: [e.g. skip hire, parking, equipment rental]
My running costs per month: [e.g. van, insurance, phone, software, or a rough total]
Days I actually work per month: [number]
What I want to earn: [e.g. per day, or per year]

Ask me up to 4 short questions first if anything's missing. Wait for my answers.

Then:
1. Work out my true cost per hour, including running costs and non-paid time.
2. Build the job price line by line: labour, materials, travel, other costs, then a margin.
3. Suggest a margin for this kind of job and explain it in a sentence.
4. Give me a walk-away price: the lowest I should accept.
5. Tell me what to check before sending the quote, such as VAT and price validity.

Show every sum, use only my figures, and mark guesses. This is planning help, not financial advice. UK English.

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