My VX5000 is also invaluable in cleaning the door hinge areas that are really dirty and full of crap that all the cars in the Northwest get in there..
Just try to stay away from the actual hinges and the grease that is on them so as to not remove too much of it... I know, it needs to look neat, but they need the grease to continue to work well and not get corroded and stuff..
Wheel wells - I prefer my pressure washer after spraying a good APC or Degreaser up around there... Steam will certainly do this too, but I still like my process..
Wheels - - I prefer my wheel cleaner and pressure washer again.. I dont want to be that close to all that brake dust coming off and I can go much faster for my needs.. Steam can certainly do this but depending on how much PSI you have, it might take longer..
Good luck !
Dan F