Power windows are an example of "use it or lose it".
The switches are easy to fix, usually just cleaning the contacts.
Like John said, epoxy it back together if the fold over tabs break off.
Nothing to lose if it is inoperative. Give it a try.
The motors are also easily repaired, usually only needing cleaning.
NOTE: The spring on the life arm is very dangerous!
To remove the motor, 2 of the 3 bolts are accessible,
the third is under the inner door sheet metal.
For safety, with the window up, put a 2X4 under the window
and the bottom of the door. This prevents the window from coming
down with your hand or arm in there
To access, Drill a 3/4"
hole directly over the third bolt. Then remove that bolt.
The motor will come off to be repaired on the bench.
The entire lift can be removed if you need to, but is a very dangerous thing.
The arm can violently swing around when the motor is removed.
The spring is there to counterbalance the weight of the window so once it's out,
the motor is the only thing keeping it from unwinding. Ask how I know!
If working on it this way, drill a hole through the lift arm and the frame of the part.
Put a bolt and nut through both to secure the arm. THEN remove the motor.
Been there and done this many times, Ray