Explain whether the issue is debris in drainage, appearance or a finding from an inspection. Identify the material and finish before selecting a method. Ask what protection, access and handling of removed debris are included. Treat repairs as a separate agreed scope. A clean appearance does not prove that all underlying roof layers have been inspected or renewed.
Define the purpose
Explain whether you want debris removed, a visible discolouration assessed or maintenance performed. Ask what improvement cleaning can realistically achieve. An appearance issue and a defect in the roofing may need different work.
Identify material and condition
The cleaning method should suit the roofing material, finish and condition. Ask what assessment takes place before choosing the method. Do not assume one cleaning technique is appropriate for every roof or decorative surface.
Check what the price includes
Ask about access, protection of nearby surfaces, gutters, installations and handling of removed debris. Confirm whether inspection is included and what is excluded. A cleaning price does not automatically cover repairs or a new coating.
Let findings determine further work
Ask how defects discovered during cleaning will be documented. Agree any repair separately before execution. A clean-looking surface is not evidence that all underlying layers have been inspected or that the roof has been renewed.
Make the expected result clear
Discuss what cleaning will change and what marks or damage may remain. If your main concern is a recurring leak, ask whether inspection should come first. The right assignment follows from the problem you actually want resolved.
Plan the surrounding work
Ask how nearby surfaces and drainage are protected and left after cleaning. Clarify what happens if damaged parts are found. Keep photographs and any separate repair agreement with the record of the cleaning work.