Prototype

"If a picture is worth 1000 words, a prototype is worth 1000 meetings."

Source: https://twitter.com/markdrasutis/status/336234035305123840

If you have a big project and some parts are still fuzzy, it’s difficult for us to make a quote.

Say a “back of the envelope” evaluation for a project is $50k to $100k. Since Tiki has so many features, we can build a prototype from existing features for 10–20% of that amount. At that point, the gaps will be clearer and we can establish priorities.

http://contenthere.net/2007/03/poc-prototype-or-pilot-when-and-why.html
http://en.wikipedia.org/wiki/Software_prototyping