Advice on buying junkyard engines?

Freezerman said
I have bought 3 5.9 engines with 135k to 170k miles on them. Bearings, rings and bores look brand new. Cam bearings are always bad. New cam and bearings, intake. Run them Hard! zero problems.

I would add new core plugs, timing chain, and head gaskets in addition to cam bearings to any used engine as well.