Cleaning up after a murder scene

I would use a bissell. 

I was called by a client who has properties.  A woman stabbed her husband 40 times in her house, and murdered him.  The home was locked for 3 months during the investigation.  She now needs to clean up the home.  It looks like a murder scene right off TV, and the smell...well it smells scary.  I have never handled something of this magnitude.  I dont want to turn the job down, but think this may be a little beyond a basic carpet cleaner.  I would think there is blood in the pad and to the floor.  The walls look like there was paint thrown on the walls and hand prints all over them in blood.  How do I even start to bid a job like this, and I would think the carpet should be replaced due to health hazzards.  Any advise?