There's a 2001 Dakota with the 4.7 in it selling for 900 bucks all because it has no compression in the number one cylinder. Is it worthwhile to buy this truck?

 

that's entirely up to your budget. you need to know why there is no compression. if its a head gasket there must be a reason for the leak. most likely over heated so the head will need to be decked strait and an overhaul of the coolant system is needed. bad rings are a little worse. personally i'd pass and spend the extra couple bucks and get one that's running

 

A somewhat common problem is the 4.7 dropping a valve seat so the valve can't close. Usually this is due to overheating. The 4.7 doesn't like to overheat.