Cracked Slab-Opinions Needed

[Jeff Valentino]

This is a house that has fix and flip potential but I'm wondering about this crack. The property is back on the market with a price reduction and rehab started.  It's about midway in the of the floor and runs across the entire basement and into the garage. It has a noticeable pitch and gives the impression that the front half of the house is sinking. There is some minor drywall cracks in the rooms above. It looks like someone did some leveling or patchwork in this pic, but I don't know how long ago that was.

I'd like to have some ammo when I talk to my  contractor. Any ideas on repairing it or other input is appreciated.