very few homes don't have foundation or shifting foundation problems. Many cracks are common and not to completely worry about and some are so severe you can have pipe burstings.
As David stated, to jump to the conclusion that you must sell is the wrong approach entirely. Because inspections by professionals will see this and red tag it and it will have to be addressed regardless before sale anyway.
Foundation repairs are not as expensive as they used to be and now days are warranted for the life of the house. Depending on who you use, one jack may cost $500, and sometimes jacks are only needed on one side of a house not all the way around. A jack is normally required every 10 running foot.
Many cracks on the exterior brick can be repaired with latex cement caulk. These cracks usually follow the mortar line in a zig zag pattern from the top to the bottom. Sometimes the crack will just crack and never grow, I call that a small expansion joint that the home has made for itself.
You need to watch the crack, measure it with a tape measurer or sticking a dowel in the crack at a certain area and doing this again on different time spans to see if the dowel is tighter or looser than before.
Seek professional advice if you want, but be careful with fast selling companies that only want your business.