Measure the actual space
Give the designer ceiling height, available wall dimensions, windows, doors, and furniture locations. Identify curtains, beds, and seating that could obstruct the proposed unit or receive uncomfortable airflow.
Ask where the unit can be serviced and how refrigerant lines, electrical wiring, and cooling drainage will reach it.
Compare approved mounting choices
For example, Mitsubishi's MFZ-KJ09NA through MFZ-KJ18NA floor-type installation manual includes specific placement and clearance requirements. Those instructions apply to those models, not every low-mounted head. Mitsubishi floor-type installation manual.
Ask the installer to provide the exact proposed model's mounting diagram. A conventional high-wall unit should not be placed low merely to fit unless its manufacturer approves that arrangement.
Other styles may be worth evaluating, but the provider must establish their structural, space, drainage, and service-access requirements. Ask for a complete installed scope, including qualified building or electrical work where needed.
Keep sizing in the decision
Request a room-load calculation and the proposed combination's usable range of output. A floor unit that physically fits may still be an unsuitable choice for a very small room.
Ask how the plan behaves when demand is low and whether a different arrangement could serve adjacent small rooms appropriately.
Also discuss temperature sensing, airflow near occupants, sound, and where furniture can remain. A diagram with the room's actual layout is more useful than a product photograph.
Resolve the layout before purchase
We would request a marked drawing showing the unit, required clearances, line route, drain route, and maintenance access. Ask the provider to identify any work excluded from the quote.
Your next step is to send room measurements and photographs for a qualified site assessment. Choose the model and placement together, with sizing evidence and approved mounting instructions in the proposal.