There is a saying 'A picture paints a thousand words', but when I first saw this image I just saw a photo of a couple in a domestic garden and though, 'boring picture'.
And then, if you look again a few more thoughts come to mind. For a start this picture seems to have been taken from an upstairs window. Initially I assumed it was taken from the same property, but when you look at the fence positions this seems to have been taken from a neighbour's window. The woman in the picture is laying on a towel and seems to be sunbathing so is this a sneaky, voyeuristic picture of the woman next door? On the grass next to the couple is a hula hoop and a dart board. Could it be that this couple were outdoor, noisy types and a neighbour is trying to get evidence of 'unruly behaviour'? I guess, like many found film images, we will never know for sure.
Regarding the date it's not possible to be precise, but the top half of the garden has been used for growing vegetables which is something which would not be done today, and suggests possibly the 1960s or 70s.
Location? This is a difficult picture to pin down to either a general or a precise location although I would think it likely that the garden shown is somewhere in the UK.