rfm
I am sorry you took offense at what was intended to be a step back and look at reality. Benchmarks in business are not hard and fast rules, but they do serve a purpose.
1) Employee "cost" is approximately 2x salary. Thus, net income for a successful business must be greater than the sum of those costs. A corollary of that is for free lance work, one must charge at least 2x his current or expected salary. There is a clamor in the US to set minimum wage at $15/hour. Using that minimum wage, which most of us would consider quite low for a skilled programmer, one gets to $30/hour for the work.
2) There is a widespread "myth" that a good programmer should be expected to write 10 lines of good code (LOC) per day. An IBM friend told me in the 80's that the LOC expected at IBM was a bit higher than that, about 30 LOC/day.
3) Minimum wage would mandate that your contractor charge at least $240 per day ($30 x 8 hours).
4) At minimum wage, your $400 = 1.67 days of work, which equates to 17 to 50 lines of code.
5) On top of that arithmetic, you probably expect the work to be "for hire." That is, you own all rights to it and expect an NDA from the contractor.
I do not think those considerations add up to a realistic expectation -- assuming you do not expect the programmer to have significant ownership in the product . If you needed that lecture, maybe your experience in business is too limited.
John