Understand that those "extra ports" can often disable the OEM functions, including remotes (which are required for proper operation for capturing VHS). The mod is not easily reversible, and sometimes not reverisble at all.
So be wary.
There were at least 3 common mods done to the MV VHS/DVD models by college/HS sports facilities. The mod was done by common sports video production companies.
It's also a common sign that the unit was ridden hard, and has zero maintenance. I've seen more bad decks than good, which had this modification. Heads are very often shredded, and thus have tracking issues, and the decks garner F/C/B ratings on my deck grading scale.
Again, beware.