Choosing and vetting a cleaning company: questions to ask

Hiring someone to clean a building or wash its exterior hands a stranger your keys, your floors and sometimes your safety. Most providers do honest work, but two proposals for the "same" job can describe very different things. This page lists questions that apply to any provider, drawn from consumer-protection and occupational safety sources, so you can compare proposals on equal terms. It does not name, rank or recommend any company.

Start with a written scope of work

The most useful document in this process is one you write yourself before anyone quotes. List the areas, the tasks in each, how often each task happens and what "done" looks like. The commercial and office cleaning guide explains how scopes and frequencies are usually split into daily, periodic and project work, and the guide to how cleaning works explains why the order of work matters.

The Federal Trade Commission advises getting more than one estimate and says a written estimate should describe the work, the materials, the completion date and the price. It adds that you should not automatically choose the lowest bidder, and that a big difference between estimates deserves an explanation (FTC: How To Avoid a Home Improvement Scam). If every provider prices the same written scope, differences in price become easier to understand.

Ask what they will use, and ask for the paperwork

A provider who brings chemicals into your building is part of your chemical safety picture. Under the US Hazard Communication Standard, an employer must have a safety data sheet for each hazardous chemical it uses, and a written program must describe how other employers on the site get access to those sheets (OSHA: 1910.1200 Hazard Communication). In plain terms, it is reasonable to ask for the safety data sheets of the products that will be used in your space. Our guide to labels and safety data sheets explains how to read them once you have them.

Useful follow-up questions include which disinfectants, if any, will be used and where, whether they are applied according to the label, and how products are kept in labeled containers. If the work is outdoors, ask what pressure, nozzle and cleaning solution will be used on which surface, and what happens to the rinse water. The pages on pressure washing and soft washing, surface suitability and roof and siding soft washing give you the vocabulary to judge the answers.

Licensing, insurance and training

The FTC advises considering only contractors who hold the required license and carry insurance, checking a contractor's license with your state or county government, and asking for proof of insurance (FTC). Licensing rules differ by place and by type of work, so ask which licenses apply and verify them with the issuing body rather than relying on a certificate the provider hands you.

Training and standards are also fair questions. The Cleaning Industry Management Standard (CIMS) is a certification run by the trade association ISSA, which says it covers operational management and, since an update, hygiene and infection prevention criteria for cleaning service providers (ISSA: About CIMS). Holding a certification like this is not required to do good work, and not holding one is not a warning sign by itself. The question to ask is what a provider's training and quality system actually covers, and how they would show you.

References, complaints and problem handling

The FTC suggests asking people you trust for recommendations, checking with consumer protection officials for complaints, and reading online reviews with a critical eye (FTC). For a building, a good reference is another site of similar size and use. Ask the provider whether you may speak to someone responsible for such a site, and what the provider did the last time something went wrong.

Then ask how problems are handled in your own arrangement. Who do you contact, how quickly is a missed task redone, how are damaged items reported, and how is a change to the scope recorded? Answers given in conversation are easy to forget, so ask for them in the proposal.

Contract terms worth reading twice

The FTC advises reading the contract carefully and asking for a written agreement even where your state does not require one. It lists the contractor's name, address, phone number and license number, estimated start and completion dates, and any promises made in conversations about scope and cost as things the contract should include, and says blank spaces should be filled in before you sign (FTC). For ongoing building cleaning, add the practical points: the length of the term, how either side can end it, how the scope can change, and how supplies and equipment are handled.

Red flags

The FTC lists several tactics used by home improvement scammers: turning up unannounced because they are "in the area", pressuring you for an immediate decision, asking you to pay everything up front or accepting only cash, and saying they have leftover materials from another job (FTC). The same page advises against paying the full amount up front and against making the final payment before the work is done and you are satisfied. Some states limit the size of a down payment, so check with your state or local consumer agency.

Two further signals are worth noting even though they are not on that list: a provider who cannot say what products they use, and a proposal that gives only a total with no description of the work. Both make it hard to know what you are buying.

Comparing proposals fairly

Put the proposals side by side against your written scope. Mark where each one is silent, since silence usually means the item is not included. Check that frequencies, areas and products match, and ask each provider to clarify gaps in writing rather than by phone. A cheaper proposal that leaves out two areas is not cheaper, and a more expensive one may simply describe more work. That is the comparison the FTC's advice to ask for an explanation of big differences is meant to prompt.

The short version

Write your own scope first, ask for the same detail from every provider, verify licenses and insurance yourself, and read the contract before you sign. Treat missing detail, pressure to pay up front and vague product answers as reasons to slow down.