ArtPog :
My impression (although it's possible I may be mistaken) is that the distribution of these manufactured HP models from HP (and their authorized HP distributors) were ALL equipped with USB 3.0 ports (possibly in addition to some USB 2.0 ports). What happened during the "refurbishing" of this or that particular unit I'll leave to others to determine.
I contacted the seller, and it turns out that the information listed in the description seems to be wrong. Apparently, the one they sold me
does have four USB 3.0 ports. That said, the information I obtained in this thread may become useful in case I ever want to add some more.
ArtPog :
Another reason to avoid "refurbished" PC equipment unless absolutely necessary for financial and/or other reasons.
In my case, it is necessary for financial reasons.