skip the carpet soaking rotovac and buy a 175rpm rotary scrubber instead.
much more versatile.
Use it to pre-scrub rat holes when needed, then extract rinse with the porty.
(that combo will do a MUCH better job than the rotosoaker)
It will also allow you to bonnet clean and encRap sCampoo.
you can strip and wax VCT with it too if the opportunity presents it's self
as far as chems, most major manufacture's chems are good.
You need a "nuclear" pre-spray for rat holes and a quality all-purpose pre-spray that can be used for stain resist carpets
If i had to choose only "one" line of chems, it would be
Prochem.
IMO, they have the most consistently good chems through out their whole product line
do you have a local supplier near you?
If so, what brand chems do they stock?
(I'm a firm believer in supporting your local economy and local supplier "if" reputable and honest)
..L.T.A.