Oil stains

The expensive and probably very un-environmentally friendly oil stain remover *does* work, somewhat to my surprise, at least to a degree. At any rate it removes the surface black and a proportion of the underlying mark, with the dabbing cloth getting visibly greyer as you work over it. The trouble is that it takes multiple applications for any 'serious' stain, with a five-to-ten minute wait followed by a one-minute wait for the dissolving reaction to work, and I have a very large number of heavily stained blotches...! I'm not sure there will be either enough stain remover or enough time and patience for me to work my way around the lot.