Possibilities:
- Seller may have modified the phone to install malware disguised as typical bloatware
- Likely to be a gray market phone direct from China
- May already be rooted

Wonder if this would work for you (flash a new ROM):
http://www.howtogeek.com/162516/how-...ith-a-new-rom/

Note: I'm a "casual" smartphone user, so any talk of rooting and flashing new ROMs and foreign to me. I understand what those mean, but haven't the foggiest clue of how to go about doing it. Took me long enough to just figure out how to use Helium