You can purchase a auto-starting kit from Radio-shack that will work with the relays and lock and unlock the doors as well as starting the engine. All she would have to do is turn the key to the 2 position and not all the way to crank.
The power steering will have to be adjusted inside the sector. I have done this before and it is not a Do-it-yourself repair. You will have to remove the power steering sector and disassemble it. Next you will have to take out the metering valve and the springs. To lighten the wheel, just shorten the springs BY A LITTLE BIT. After this you will have to reassemble the sector and set up the proper clearances. This is not easy. I have some specail tools for this.
A tech/shop may charge you about 5-600 dollars to do this, but that would include a set of o-rings to reseal the sector as well.
ASE CERTIFIED MASTER AUTO TECHNICIAN
MERCEDES SPECIALIST 11 YRS