Agree, NBD. I have a brompton and have some surface rust in the interior tubing due to a high humidity location I visited for 6 weeks. The rust on the inner portions of the hinge flange are from the paint rubbing off and being bare metal.
My advice is buy the bike and use a large cleaning brush with some rust preventative on it and scrub the interior of the tubes. Most of it will disappear and prevent surface rust in the future.
Last edited by DAME; 04-23-15 at 04:04 AM.
Reason: spelling