Hi Ian
I do a fair amount of office tiles, and primarily I use Dry Fusion. On their training course, D/F reckon that you could charge as low as 60p sq.M and make a profit. For my set up, regardless of the size of the premise, I wouldn't be interested in the price sensitive area of the industry. I'm not saying that Dry Fusion advocate charging 60p, just that it's possible.
My approach is to quote initially for a "restorative" clean at full price. With the quotation, I would also include advice and quotation for a maintenance plan. As long as it's about 200sq.M+ I would do this at approx half the price of the restorative clean. When I started with Dry Fusion, consumables were a little more expensive than they are now (some things do come down!) and I was keen to build up a client base for my new service. On one site I was charging as low as £1 for maintenance at 6 months. I'm now charging considerably more but won't discuss my prices in public.
I feel that a business decision for an office cleaning company to venture into Dry Fusion is sound and viable. It's easy, low cost training is availble, and can be exceptionally profitable. All you need to do now is go out and sell it.
Safe and happy cleaning:)
Ken