Quoted daily ("Work is on a time and materials basis. Rate: $2,000 per day."). Invoices will typically cover a few weeks of work, depending on the tempo of your engagements, your relationship with a customer, etc.
This has to be regionally dependent. Around here there is no way you would get $2,000 day for web development. Best I have ever gotten is half that, for a one-day "emergency" engagement (i.e. drop everything and help me).
I just plucked a number out of the air, rather than picking a number which I felt was representative of web development.
Also, I've harped on this a time or two, but there are people who get $2,000 a day for something which is indistinguishable from web development in terms of activities performed but which is sold as accomplishing business goals ("making lots of money") with incidental reference to programming.
P.S. Charge more for emergency engagements. The business stopping for a day is worth more than $1,000 even if the business is a taco truck. Don't do professional work for taco trucks.
patio11, I'd like to say much of my stance on negotiating rates with people has come directly from reading comments you've made on hacker news in the past. Thank you!
If anything I still think I'm too lenient but this I'm sure will grow as my confidence dealing with clients grows.
indistinguishable from web development in terms of activities performed
You're over-discounting domain knowledge. Anyone can write in code x+y. It might take much deeper knowledge to know that sometimes, it's x-y, and exactly when that is.
Lots of WordPress (yes, WordPress) devs charge $250/hour. That's $2,000 (assuming no travel expenses). JavaScript/Ruby/Python, I don't see why $2K/day is actually not feasible.
Are you aware that there are lots of Indians willing to do work at $5/hour? There are $10 watches in the market, but that doesn't mean that $2,000 watches don't get sold.
And there's no end of students (even students with honours degree in computer science) who don't know the first thing about programming. That's why "how to do interviews" and fizzbuzz questions are a popular topic on this site.