The area alone is not enough to explain the work. Ask for the included repairs and preparation to be identified.

A wall with well-adhered paint and one with flaking parts do not need the same preparation. Before requesting a quote, describe what you see: lifted areas, old repairs, visible cracks or differences in finish. You do not need to diagnose the cause to indicate where review is needed.
In its Aguaplast Renovación data sheet, Beissier requires a firm, dry and clean substrate and a check that existing coatings are suitable. This guidance applies to that material; it does not establish a universal procedure for every wall or allow the product to be chosen from a photo.
Separate tasks in the proposal
- Protection and moving of furniture, as agreed.
- Removal of poorly adhered parts and repair of specific areas.
- Preparation or primer that the company considers necessary.
- Applying paint to the specified surfaces with the agreed finishes.
- Clearing and cleaning the work area.
State the location and approximate extent of each issue. “A repaired area of about 50 × 50 centimetres next to the living room window” provides more information than “the wall is in average condition”. The company can locate it and assess the preparation needed.
When the cause of a mark is still unknown
If there is a stain of unknown origin, explain how long you have noticed it and whether it has changed. Ask for it to be assessed before specifying the finish. Do not present painting as a confirmed solution to a problem that has not yet been identified.
Check whether the quote includes all the preparation described or leaves some tasks pending a visit. Phrases such as “touch-ups” or “walls ready” may not be enough to know what will be done. Ask for clarification about those areas and keep the agreement with the quote; this avoids comparing a complete proposal with one that assumes a prepared substrate.