No luck unlocking the device. It is a new security feature like Apple. The eBay seller says to return it. Google can not unlock it. Probably they won't cooperate with CIA or FBI either just like Apple didn't. Still,thieves can get through except for the users. I've seen a lot kids on Youtube showing how to unlock various phones and tablets.

I live in a gated community. At times, residents, friends, and relatives can't get through but the thieves can. Now they have a guard 24 hours at the gate, which is nice, but it costs more.