The REQUEST QUOTE Version 2.0 Extension for OpenCart provides following feature
• Allows Customers to request quote for a product
• Manage Quotes via admin menu
• View product options for each quote
• Respond to Quote
• Manage Quote History

11/18/2014 - Updated Extension for Opencart 2.0

DEMO:
http://www.mintegra.com/quote/

Admin Screencast:
http://www.screenr.com/kHXH
DOCUMENTATION:
http://www.mintegra.com/support/docs/Quote_User_Guide.pdf