Being able to build something quickly to put in front of users, gives companies a great ability to test many different theories, even with fairly limited traffic. One of those theories that Thumbtack had always wanted to test was the concept of a Kayak-style business model in the services sector. We first started out by figuring out which professional fields that exist on Thumbtack already, could fit a set price model. Most of this investigative work was done by my number crunching product manager. After determining that resume writers, and later DJ's, fit this model well, I started out on a quick round of high level wireframes done in Balsamiq.
After a day of working on the wireframes, I presented the small team (myself as the designer, a product manager who oversaw the details, and an engineer) a round of 10 different high level concepts. From these, we were able to pick out a basic feature set and interface ideas to allow us to move to the next step, html design and back end coding. While the engineer worked on wiring up the backend and payment system, I designed and coded some quick html prototypes in the browser. After a day of polish, they were handed off to the engineer for final wiring up. After a day or two, it was handed back to me for final polish. So, basically, within a week, we were able to go from high level concept to a production ready feature that we could put in front of users to learn.