Photographing a small flat so it does not look small
Most of what people do to make rooms look bigger makes them look distorted instead. What works is duller and better.
Most of what people do to make rooms look bigger makes them look distorted instead. What works is duller and better.

The instinct with a small room is to go as wide as the lens allows. It is the wrong instinct, and it is the single most common reason a flat looks worse online than in person.
An ultra-wide lens does make the room appear bigger in the frame. It also bends the verticals, stretches whatever is at the edges, and puts the far wall further away than the eye would ever place it. The buyer does not consciously notice the distortion. They notice that the room was disappointing when they stood in it, and that the photographs cannot be trusted, which quietly discounts every other listing you have.
In a small space every object costs floor area in the photograph. Not just the obvious things, the drying rack and the bin, but the ordinary ones: a kettle and a toaster on a short worktop, four cushions on a two-seat sofa, a bath mat. Clearing surfaces does more for perceived size than any lens choice, and it is free.
The honest summary: you cannot make a small flat look big, and trying is what makes it look bad. You can make it look bright, straight, well-kept and worth a viewing, and that is what sells it.
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