It's the motor/regulator for sure.

I've replaced 5... thats what they do.
They arent that expensive, and you can get them online pretty cheap. Just make sure you get the one that's specific for the window you're working on.

Pop the door panel off, remove that plastic shield, unbolt the motor/regulator assemby, and disconnect it.
And swap out the new one. Fairly straight forward, and it's way easier if you tape the window in the up position.