are these stains or dirt? some stains can not be removed ie dyed the carpet, it just sounds like a trashed carpet to me dirt will allways come out with hwe, allways tell the custy sometimes not all marks come out before u start to clean, sometimes a carpet is just to far gone and abused , most good powered hwe chems will get lot marks out with good heat, the prob u can come up agaist with a trashed carpet is so many marks caused by so many diffrent spills and u cant tell what each one is to start using 100 diff chems so just use strong chem and prespray like prochem doulbe clean/heat wave/power burst and steam the hell outter it !!! and tell the custy its the best it can get
p.s u are turning the vacs on ?
