Here's a pedicab that appeared briefly on Ebay. It had a number of bids, was up over $1,000 when the listing disappeared- not sure what happened to it:
Normally, these things are listed as "pickup only", not shipped. That means if you're in an area where they're using them, there's a demand and prices should be good. Otherwise, there's no telling. Similar with some other oddball cycling stuff- trikes and stuff.
In the Unility Forum, I had a post a while back called "Pedicabs Etc" with a link to a list of manufacturers- you can peruse them and get ideas of typical prices new.