Small properties ask us for this regularly and the advice is nearly always to use less than they were planning.
What works is one light scent used consistently in the public areas and nothing at all in the bedrooms, because a guest with a headache in a room they cannot air is a review you do not want. Reed diffusers in reception and the corridor, refilled monthly, and a room spray used before a changeover rather than during a stay.
We quote by the property after somebody has walked it, and the quote says how much refill you will use in a month so the running cost is visible before you commit.
We will also tell you when the answer is no scent at all. A dive centre smelling of neoprene and salt is telling the truth about itself and covering it with amber helps nobody.