To me my Vanagon Weekender is a VAN and not a BUS.

Reasons:
(1) A bus to me has all forward facing seats, my van has two rear-facing
seats.
(2) A bus to me is just a people carrier, not a cargo carrier. My van
has removable seats and lots of cargo room.
(3) With the current popularity of passenger mini-VANS, the term 'van'
has long since lost its sole meaning as a windowless cargo carrier.