School of Life Hacks
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    Gloved hands reaching into the opened rear panel of an appliance, a row of screwdrivers laid out on a folded towel, a green work light overhead.

    Repair or Replace

    The arithmetic that decides, written down before you are emotionally invested in a machine you have already half disassembled.

    Module 7 of 74 lessonsWritten in full1 worksheet
    Start this moduleThe whole course

    The lessons

    All 4, in the order they are read.

    1. 1. The fifty-percent rule, and why it is usually wrong
      The rule of thumb ignores remaining service life, which is the variable that actually decides.
    2. 2. Parts availability as a signal
      When a control board is on back-order everywhere, the market is telling you the machine's service life is over.
    3. 3. The jobs worth paying for
      Some repairs are cheap in parts and expensive in consequences, and a professional's insurance is part of what you buy.
    4. 4. Keeping the record
      A machine with a written service history is worth more, fails less, and is far faster to diagnose the second time.

    The worksheet

    Repair-or-replace calculator

    Fill both columns before you order a part. The decision line at the bottom is the whole point: it is computed, and you write it down while you are still able to be objective about a machine you have not yet taken apart.

    Repair-or-replace calculator
    LineRepairReplace
    Parts cost—Purchase price
    Labour: your hours x what your time is worth, or the quote—Delivery and installation
    Disposal or trade-in——
    Total cost——
    Expected remaining service life, years—Typical service life for the class of machine
    Cost per remaining year= total / years= total / years

    3 further rows in the downloadable sheet.