OP, I know that area and it is so lovely. Nothing in those photos suggest this.
The flat looks very tired, cheaply done up a while ago. The garden is unloved.
I'd put some effort into it. Buy some pale sage green paint and paint the living room or main bedroom or both. Steam clean the carpets to raise the pile. Do something to make the kitchen look a little less jaded. New cupboard doors and worktops would help.
Have photos taken that show access to the garden. A photo of bathroom is also needed.
Mow the lawn. If it's possible to put up trellis or something to mask the hideous view on the other side of the garden, or to take photos of the garden that don't show it looming, that would be good. And add some photos of Trent Park lake and the cute cafes on the High Street, so people get a sense of the location.