Name of Home directory of previous owner of MacBook Pro
The correct thing to do is wipe the machine &amp; start over.
That way you would at least own the OS. 

Right now, everything on there is registered to its previous owner, which is going to cause problems for updates, even OS updates, unless you also know the previous owner's Apple ID &amp; password [which I sincerely hope you don't]

Apple &amp; Microsoft run opposite paradigms, Windows essentially ties everything to the machine, Apple ties it to the owner.
This makes moving machines very easy on Apple, but changing owners much more difficult, &amp; in many cases impossible.