Office cleaning is one of those purchases a small business makes once, badly, and then lives with for years. The service is invisible when it works, so the contract only gets read the week you want to leave it.
The specification is the contract
Most disputes trace back to the specification, the list of what gets done and how often. A vague spec ('office to be kept clean and tidy') means the standard is whatever the cleaner decides at 6am. A usable spec names tasks and frequencies: bins daily, desks weekly, carpets quarterly, kitchen appliances monthly. When you compare quotes, compare specs, because the cheap quote is usually cheap by omission, and you will buy the missing tasks back later as extras.
Ask what happens when your regular cleaner is off. Established firms have cover staff and a supervisor who inducts them into your building. One-person operations, honest ones anyway, will tell you the office just doesn't get cleaned that week.
Notice periods and the exit
Twelve-month terms with ninety-day notice windows are common, and they auto-renew. Diarise the notice date the day you sign. If you are switching from another contractor, ask both firms about TUPE before you commit: in the UK, cleaning staff who spend most of their hours at your site can transfer to the new contractor with their existing terms, and it applies to small contracts more often than either side expects. A contractor who shrugs at the question has not dealt with it before.
The bin bag question
It sounds petty until the first invoice: who supplies consumables? Bags, hand soap, paper towels and toilet roll can be inside the price, itemised at cost, or marked up healthily. None of those is wrong, but you want to know which one you are signing.
Commercial cleaners on this site list the sectors they cover and the areas they work, see firms near your office, or send the same brief to several at once. Write your specification first, then invite quotes against it. It is the single change that makes the quotes comparable.
