Definitely go to
www.graflex.org to learn about the models and how they function. Also watch YouTube videos about their operation. A neophyte might not even know how to open one up (not saying that's you).
It's a simple camera, yet its versatility complicates learning about all its features. For example, there are four ways I can focus my Pacemaker: the focusing rails, the rangefinder, the groundglass, and the light beam.
My understanding is that the bellows on these are rarely a problem, but good to check anyway. Also check if the back is Graflock or something else.
Let us know what you find!