Should cracks and water in the crawl space concern me when buying a house?
The simple answer is I would never buy a house without a proper inspection by a licensed inspector. In some areas, you can find engineering firms that will do both structural and mechanical inspections and could tell you if those cracks are a problem. I suspect they're not, given that concrete is expected to crack at some point and part of the point of the metal reinforcement is to mitigate the effects of cracks. But if the cracks are prevalent across the foundation walls, I might be concerned. Get a professional opinion. The few hundred dollars you spend on an inspection could save you from financial ruin.