the rebuilding is on the old ones,
often either there broken or missing it's called a belly pan . drip pan and also holds the center drawer
The hole is to access the bobbin, the imports from Asia had these, Pfaff uses this so did necchi,, singers never had that hole.. when singer went to ele cabinets you could access the bobbin from underneath
Mike is correct about that stand. the machine and cabinets is knockoff. I can only guess by the huge cap between the center piece ( drawer) and the side drawers that this one came with wooden legs. which where wiggly someone replace those with a stand
The point was only ID ing what it is not the value . also note how big the hole is at teh belt, this was for the handwheel the pan is closer to the top than a OG cabinet