I have heard of some collectors trying to get more than 2 ounces from people before but this is rare, like 1 out of 200 and against procedure/guidelines. Most urine tests now are done with a split sample, one vial containing 30 ccs and another vial containing 15 ccs. A lot of collectors will just put 30 ccs in both vials. Any collector asking for more than this is full of shit and just messing with you because they know substitution goes on. I would rather do 2 ounces and be comfortable than a 3 ounce bottle pushing on the back of my scrotum.