You are basically promoting a product your rentals so the first question should be what is your market? Once you have that set then are the properties not capturing your market or you think your capture should be bigger? Then we would have a better idea if a garden or a better bed?
@Marie8425 has brought up a very interesting point about market research. Please let us know when you can review our message and update us on whether you have already done market research or if you plan to do so in the future.