Early in my construction career and later on in my home flipping endeavors one tool that was always essential was my drywall lift. Being a contractor, who often found himself working alone on projects maneuvering a large 8 foot by 4 foot sheet of drywall was never easy. My lift allowed me to stage and hold sheets in place so that they could be secured to the wall without any risk of damage or injury to myself.
Drywall lifts our composed of three pieces, the base which is on wheel that allows you to move the lift around even when carrying a sheet. The base provides wheel locks to prevent it from moving. The lift, which is actually the unit that lifts the unit up and down by cranking it the wheel up or down. There is also a locking mechanism on this that you can flip over and slightly snug the lift to to keep it from flying open when carrying it. Lastly You have the arms which are what hold the actual sheet of drywall. In the photo of the one I have the arms will expand to accommodate a twelve foot sheet of drywall. This is extremely useful as it would not be possible to hand a twelve foot sheet by yourself.
It is rather difficult to maneuver a twelve foot sheet of drywall so I would highly recommend eight foot sheets by yourself. When you are using you lift it does have small arms that allow you to hang sheets on ceilings and walls alike. The trick to put enough pressure on it and then put a few screws in before letting it go. It is designed for placing ceilings in but I have found it will assist in lifting a sheet up in a corner snug and I can then put pressure on it and slide on top of the other sheet and screw it pretty easily.