Congrats! What a find! Post some pics! Auto or Manual? If the oil and filters haven't been changed recently (last 6 months) I would do that 1st. Then just drive it and watch for oil/fuel/tranny/coolant leaks if it has been sitting for awhile it may have some dried out seals.
If he's kept it drove and maintain you should be good to go. Get a couple of fuel filters and keep them in the truck. Fuel maybe a little stale if it's sit for long periods. Word of advice use the Ford Motorcraft fuel filters ONLY. Aftermarket filters have a tendency to put to much pressure on the bottom of the fuel filter housing and will short out the heater in the bottom of the housing. If it shorts out it will blow a fuse and truck will not run. Learned the hard way I shorted mine out twice. Last time I just left the heater unplugged so it wouldn't do it again. Others may chime with some advice but this should give you a good starting point.
Ford had recall on the CPS sensor also but it may have already been done. Ford maybe able to tell you if it was done already. They replaced both of mine on my two 7.3's Again Congrats!