I read a book called "The madness of crowds" which described the South Sea bubble, and other disasters. One man set up an office and made a share offering "for a highly profitable venture but no one to know what it is". He was flooded with people willing to put 20% down. He took a pile of cash on the first day and, not wishing to push his luck, cleared off with the loot on the evening boat to France.
Scammers must be all over this ASIC mining rig business. I would go pick up a rig in person. But paying up front seems too dangerous.