Foreclosure auction - risk reduction

[Vikram C.]

When buying at a foreclosure auction, I have several risks and most of them are controllable. I can figure out the ARV with some degree of accuracy, I can check for title, senior liens, etc.

The big worry for me is the risk of underestimating the repair costs. Vacant properties can't be inspected and occupied properties may end up with the resident vandalizing the property before leaving.

Any idea how to control these risks? Or do you just assume a certain percent of ARV for repair and hope that, over many properties, it will all even out? (I assume it is illegal and perhaps dangerous to break a window and go in and inspect a property that seems vacant.)