Foundation crack
 

We are thinking of buying a 1979 home with attached garage. My biggest concern is the front corner of the garage appears to have a large (1/2") vertical crack or gap in the foundation. Here is a pic from the inside:

https://i.imgur.com/GPJRWg6.jpg

Unfortunately it's not accessible from the outside as there are concrete steps to the front door wrapping around the corner of the garage. This would be a problem if it needs any fixing from the exterior.

The garage and driveway pads are cracked up and sunk several inches in that corner (and the other, but no crack there). The pad sounds hollow so I'd guess there's a void in the corner. Appears there's no rebar dowelling into the footing.

If purchased I would hammer out the concrete pads and repour them, fixing the driveway so water wouldn't pool there anymore. Just not sure about the foundation. Does it need fixing to prevent ongoing issues or is this a minor issue? How would it be fixed?

If it was just the garage I wouldn't care, but the upper floor of the house extends over it so this foundation is also supporting that.

Thoughts appreciated. I'll be going back to check things out in more detail before deciding to go through with purchase or not.

concrete
 

Drive way pads can be leveled by power jacking, quite simple, not to costly if not in real rough shape. Foundation could be repaired with little concrete patching if not shifted. Normally better concrete repair firm can evaluate it properly and provide reliable estimate. It can either be a Big $$ problem or minor repair.