My 21 year old son recently leased a 2016 Chevy Silverado. He did all the paperwork, and drove the truck home the same day. Now 3 days later the finance guys at the dealer call. They say they now want a cosigner for the lease agreement. I would never let him default on the lease, but the deal was he would do it on his own. He has a full time job coming out of college middle of May. He also has established credit for 3 years with a major credit card. My question is since the deal is already done. Can the bank legally compel him to get a cosigner for his signed lease agreement?