So the first thing we need to isolate, in terms of a squeak, when we're turning the steering wheel, is it inside the cabin, or is it outside?

So the rotten egg smell typically would be more like something from the exhaust or something so I would recommend that you first of all make sure you can determine where the odor is coming from. Is it coming from outside of the car and being brought into the cabin or is it something from inside.

First of all take a look at your wiper blade and see is the rubber still flexible or is it really stiff? If it's really stiff, some fresh blades are probably in order, especially here in Mesa, Arizona we tend to see them dry rot. Secondly if you run your blade about halfway up the windshield, check to see if it's making contact all the way. If not, there may be some issues with the arm itself that holds the rubber.

"Why does my cruise control have a mind of its own?!"

How to check if a brake booster is working.