Somebody is marking this against a standard, not reading a price

One commercial extract installation is £6,625. Our Booked package is £99 a month — £1,188 a year. That job covers more than five years.

The leverage is in which shortlists you reach. A ventilation company that reads as competent to specifiers gets invited to quote work it currently never sees, and those are the jobs with the margin. Winning one additional commercial project a year pays for everything on this page several times over, and the difference is usually the submission rather than the capability.

A commercial kitchen extract system cannot be cleaned while the kitchen is running. Which means the real variable in a £515 duct clean is almost never the ductwork. It is when you are allowed in.

A restaurant that closes at eleven and opens at eleven gives you an overnight window. A hotel kitchen that serves breakfast gives you less. A hospital or care kitchen may give you nothing at all without a planned shutdown, and a school gives you six weeks in the summer and almost nothing the rest of the year.

Quoting all of those from the same day rate is how this work quietly loses money, and it is why cleaning contracts get re-tendered — because the first year was priced on a hope about access and the second year has to correct it.

The document should say what it assumes. Which hours, how long the window is, what happens if the kitchen overruns and you lose two hours of it, whether the system can be isolated, and what an aborted visit costs when the site is not ready. None of that is unreasonable to state, and stating it is what separates a contractor who has done this from one who is guessing.

It also makes the quote comparable in the client’s favour, which is worth pointing out to them. A cheaper price for a daytime clean that cannot actually happen is not cheaper. It is a visit that will be rearranged twice and then re-quoted, and a catering manager who has been through that once will recognise the description immediately.

There is a scheduling consequence too, and it is the part that decides whether the work is profitable rather than merely won. Access windows cluster: almost every restaurant in a town wants the same overnight hours, and schools want the same six weeks. A book of cleaning contracts sold without regard to when each site can actually be entered produces a calendar with three impossible weeks in August and long gaps either side.

Quoting the window rather than the job is what lets you build that calendar deliberately — taking on the hotel that can offer a Tuesday afternoon shutdown at a rate that reflects how useful that is to you, and pricing the sites that all want the same August fortnight to reflect how little use the fourth one is. Most contractors discover this after a year of saying yes to everything, and by then the rates are set.