> Ahhhh.... incremental development and/or rapid-application
> development ... my favourite way to do things when possible!
>  Slurp!  But I'd really say no to this on a 1-week-ish project

For short-term project payments, how about

1/3rd up front (at least then if the customer just "disappears", like
they do sometimes, you're not out of pocket for components and
initial efforts)

1/3rd on completion and/or first hand-over

Final 1/3rd after another week or so of customer testing. If you
don't trust people, include some disabling feature dependent on
usage or time that's removed on receipt off final 1/3rd

When the customer signs off on what was originally agreed to,
any (major) changes/additions could be considered a new job

Oh, and slip a business card into the unit. I've had a couple of jobs
out of the blue that way. Someone has a look in there a few years
later, sees the card........

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