Know the item, not just the location
Start with the dimensions and weight of the item. A shallow display shelf and a shelf full of books place very different demands on a wall. A mirror may have specific hanging points or manufacturer instructions that affect the fixings and position.
If you are still choosing the item, keep the product link. Check what brackets and screws come with it, but do not assume the supplied fixings suit every wall. Discuss the intended use before a fixing method is agreed.
Describe the wall as far as you can
It is fine not to know what is behind the surface. Say whether the wall feels solid or hollow, and mention any previous damage, damp or areas that have been repaired. A photo of the whole area can be more informative than a very close view.
Do not drill exploratory holes or remove fittings simply to answer a question. Hidden cables, pipes and the condition of the wall need proper consideration. If the location is uncertain or unsuitable, a different position or a specialist may be needed.
Plan for everyday use
Think about what sits below and beside the fitting. A shelf above a desk needs a comfortable height. A curtain pole needs room for the fabric to open. A mirror should work for the people using it, not just the empty space on a wall.
Use a simple sketch or measurements from a fixed point to explain your preference. The final position should be checked with you before drilling. In a rented home, get any required permission first and keep the relevant instructions.
Make space for a sensible decision
Keep the intended area accessible and the item available for inspection. Mention awkward access, stairs, unusually heavy pieces and whether another person is needed to move it. Do not lift a heavy mirror or furniture item alone to get ready.
Some work belongs with a dedicated installer. Very heavy or fragile items, structural alterations and any work affecting fire safety need the appropriate expertise. An enquiry helps establish the next step; it should never pressure you into a fitting that has not been properly assessed.
