Existence of a CV in there IS evidence of someone using it before.
Suggest do a full OS reinstall, which will eradicate any and all previous users.
I had a similar situation long ago.
A used desktop of the Return Rack,
I asked the salesman - "Has this had a full OS reinstall?
'Oh yes, we do that will ALL returned systems'
Later, asking the manager - 'Absolutely, Sir. That is our standard procedure'.
Later that evening, at home, poking around in the Registry.
Find a previous owners name, address, phone num, credit card num, etc. Apparently he had bought and registered something, and it was stored.
So...the sales people LIE.