Stereo & Electronics - Loose defroster button

The 99 I was looking to buy appears to have had some stereo equipment installed at one point. The door panels are somewhat loose (longer screws fix this? the screws seem too short to fit in, they just sort of sit there)

The central panel was cut, and a cd player was installed. The traction control button seems to work, but the switch next to it (Rear window defroster, I think) just slides in backwards.

Is this a difficult fix, or has anyone else had a similar problem?

Run, don't walk, away from that car! Anyone who butchers their car like that for a stereo installation (especially since it's entirely unnecessary with the right adapter kits) doesn't care and will not have taken good care of the rest of the car.