In short: Room occupancy and bed layout are separate questions.
Ask what the room actually contains
A room sold for three or four people may use different bed arrangements from its standard photographs. Ask for the specific booked room category, the number and type of beds, and whether any are rollaways or sofa beds. Do not assume every guest has an identical bed.
Also confirm whether child occupancy includes a bed and whether breakfast is included for each person. These details affect both comfort and the comparison between quotations.
Think beyond the overnight stay
Picture suitcases open, someone resting and everyone preparing to leave. Check circulation space, bathroom access and the route to lifts. For someone using a mobility aid, obtain suitable room and bathroom details directly from the property rather than relying on the room label.