I'd go with Mike on this one too.
Low profiles do respond well to LM systems. Modern chemistry means that you can offer a stand alone maintenance plan/programme with LM where as in the past the LM was just an interim "freshen-up" ie extraction was still required at the end of the year.
I've maintained 2 buildings in the past of 39K and 40k sq' and resoiling was never a problem.
My regime was:
3 months Entrance/reception, stairways & lift, rest areas and main walkways through open plan offices. Clean any spillage areas as required.
6 months As 3 months plus all workstations
9 months As 3 months
12 months Wall to wall everywhere.
Every building will have it's own requirements, so the plan above can vary considerably.
Presuming that the work will be weekends, that's 64 weekends spoken for per year! Plan for 2 days for the 12 month clean on 40k sq'. Obviously logistics/furnishings etc. etc. can influence this.
On the larger premises, I prefer to work as a team of 3. One to vac, one on the rotary plus myself spraying, dunking pads, fetching water, moving chairs etc. etc. You have to do everything possible to prevent the rotary from stopping.
I use Dry Fusion and also generic bonnet cleaning. My preferred solutions being a microsplitter or DFC. For DFC, my Chemspec Distributor tells me that it actually treats old detergent residues as a soil rather than reactivating it, so by removing it along with the soil. I've only used it for one significant job which was 1200sqM mixed nylon cut pile and loop pile tiles. and I was delighted with the results.
A T/M will perform amazingly in this environment too, but you'll possibly need to refill and dump on site, have hose management and security issues to consider, and may find that it would not be feasible for all sites.
Safe and happy cleaning
Ken