Advice on buying junkyard engines?

My experience has been the best junk yard pulls are the ones that have a real good warranty and cost more. My salvager is connected nationally and sells parts pulled at other yards which gives one a larger pool of parts to choose from. Also ask if they have an extended warranty. In my opinion, you get what you pay for. Salvagers pretty much know how good something is from the overall condition of the vehicle, any service records in or on the vehicle and the reputation of the owner that sold them the vehicle.