It is rectangular. The available product information refers to a standing trampoline with a length of 305 cm, and the matching Salta Comfort Edition in this size is listed as rectangular.
You can get pretty close to the house wall, the net is inside the beams and the beams go vertically upwards from the outer edge. But I would still allow 5-10 cm. When jumping, the whole frame moves a bit and a little leeway is always good.
Can't answer that... But: when the protective net is installed, it will probably be quite awkward (impossible?) to pull a protective cover over it. We will simply leave it unprotected outside. The protective net in particular is almost impossible to pack away, as the upper edge, once assembled, can hardly be taken apart.
This is coming a little late now... I was just outside and measured it: The jumping net is at a height of about 90 cm, the overall height is 2.75 m. This means that the height of the net given by them is about right.