Going to view a job were large patches of oil are running through the carpet.The enquirer said its not smallish spots but largish patches.

Its a rental so probably PP/Synthetic.
Whats the chances of these patches improving?
If they wont come out on an initial clean is there anything else to try?
Going off what hes said they are too big for spotting with a solvent ect.
Might be best to walk I think.
Thanks
Wayne