Agile modeling needs lots of "whiteboard" space -- but that does not imply one needs official whiteboards. The most simple alternative is "whiteboard sheets".
THESE MAY TAKE AWHILE TO RECEIVE, SO BUY EARLY.
THESE MUST BE PROVIDED WITHOUT SUBSTITUTION.
Here are the best brands to buy (usually you can buy these through Amazon/etc):
* (BEST option) Wizard Wall *Refill* Rolls 40 ft. -- no need to buy the original box. The full name is ** Wizard Wall Dry Erase, Reusable Static Cling Sheets, Jumbo Refill Roll, 27.5" x 40' **. Buy them at Amazon, here's the link
* (ok option - Europe) Magic Whiteboard. http://www.magicwhiteboard.co.uk
* (ok option - North & South America) Magic Whiteboard. http://www.magicwhiteboardproducts.com
* (ok option - North & South America) Smart Sheets. http://www.smart-sheets.com/
* (ok option - Asia) Easy Citi. http://item.taobao.com/item.htm?id=6747230658
if that is not possible, other options (all inferior to the above):