lorenzo simon , 34 , forced tenant michael spalding to decorate his flat .
police said simon forced him to work up until midnight like a ` slave '
but following an argument , mr spalding was stabbed and dismembered .
after hacking him into pieces , simon stuffed the body parts into suitcases .
police also discovered pieces of bone inside a drum used for bonfires .
simon was today found guilty of murder and will be sentenced next week .