Check for rust on that thing. Dealers don't price cars low for no reason.
Great deal if it do be from a dealer haha! Wonder why the price is what it is. Makes me almost think it's too good to be true but you wouldn't know unless you get a good bumper to bumper look at the truck. I would second getting it checked out as well as I'm suspicious of the price.
Some things to be aware of with that F-150 with the 5.4L 2V engine:
https://repairpal.com/2001-ford-f-150/problems
https://www.carcomplaints.com/Ford/F-150/2001/engine/
https://www.carcomplaints.com/Ford/F-150/2001/recalls/
https://www.carcomplaints.com/Ford/F-150/2001/tsbs/
Spark plug ejection:
https://repairpal.com/tsb-for-possible-ejection-of-spark-plug-from-cylinder-head-518
http://www.fordproblems.com/spark-plug-ejection/
Low mileage for the age. Have a mechanic check it out.
Have a mechanic inspect it and bring the price down a bit. Ideally you should get your hands on service records and make sure it has been maintained.