I waited for Eddie to complete his reply and he's saved me some typing. There are a lot of badly designed driveway exits. If it's not high walls, it will be box hedges.
There are good ones, with a semi-circular cutout, to give visibility but they are (generously) sacrificing several square feet of front garden to do so. Well done them.
It is an intriguing question. Scooters can move faster than pedestrians, meaning more risk of catching out an unwary car driver. Scooters have special dispensation to be on the pavement when they, otherwise, must obey the highway code. The answer might be in the documentation for the special dispensation.
My opinion isn't a proper answer but, since the scooter is the one already using the highway and the car is the one approaching the highway, the scooter has right of way.