What you are actually buying
An outcome rather than a person's time, and everything that follows from the difference.
Reads as a businessReads as employmentCuts both waysDepends where you are
Four factors, and no total. Every bar is the same length: the side is the claim, the size is not. The distinction everything else in this collection rests on.
What You Are Actually Buying
A defined result rather than a quantity of attention, and nearly every difficulty here comes from buying one and behaving as though you bought the other.
The Outcome You Have to Describe
If you cannot write down what finished looks like, you have nothing to accept against and nothing to reject against, and only standing over the work is left.
Paying for Time, and What Comes With It
A day rate is a pricing mechanism, but buying attendance rather than a piece of work changes what the arrangement is, and the difference shows from outside.
Who Carries the Overrun
Somebody absorbs the cost when work takes longer than expected, and which side that is tells you more about the arrangement than the agreement does.
The Agreement Nobody Reads Again
Most contractor agreements are signed once and never reopened, so the document describes the arrangement on the day it was written and nothing keeps it current.
What the Rate Has to Cover
A contractor's rate carries costs an employer never sees on a payslip, and reading it as a salary divided by working days misjudges the price and the person.
The Supplier Who Is One Person
Buying from a firm and buying from one person are commercially identical and practically different in every way that matters. The second is the hard case.