Hi again TCS
Whilst I agree 100% with Richie about the advantages of rinse/extraction, whether T/M or porty, I still feel that a quality LM system would be a better business decision for someone to maintain carpets on a monthly basis. You don't need a sledgehammer to crack a nut.
I do quite a bit of maintenance myself ranging from 3 monthly to annually and it's all done with Dry Fusion and quality & durability of clean are not a problem.
There is however an area I would disagree with Richie and perhaps others, and that is regarding vacuuming.
In the contract cleaning environment, timing and costing do not, IMO, allow sufficient time for a carpet to be vacuumed to the higher standards required by carpet cleaners. My experiences tell me that the typical office cleaner will use a cannister type of suction only vacuum and because of the time restrictions will at best only remove surface litter and debris from the carpet. For high quality carpet cleaning, as taught by IICRC, NCCA, Woolsafe, HydraMaster, Prochem, Chemspec et al, it is necessary to use a twin motor upright style vacuum with a beater bar/brush, and to be used correctly, not just a "quick wizz over".
My advice, TCS, is to explore the options with Low Moisture systems. You'll find that most manufacturers have something to offer.
I'm willing to bet that there are more office carpets maintained with an LM rotary machine than any other. The quality and appearance of their work is more down to the tecs. and their training than the actual tools they use. Rinse extraction requires a higher knowledge and skill level than any LM system.
Safe and happy cleaning
The Ken