When we moved into our terraced house, our next door neighbour told us that the wall that separates our rear gardens was built by her, deliberately inside her boundary. It looks like it is right on the boundary but we do not know and that is not the issue. She constantly tell us we cannot lean or attach anything on our side of the wall, It is 5ft tall solid single skin brick wall. She climbs up, leans over to see in and then writes to us aggressively threatening to get professions in to remove the attachments and charge us or engage us in legal action and us paying her costs. To be nice, we removed a small piece of lattice (less than 2ft tall), we attached to the wall to train a plant, then removed a wire we had run along the wall to get power to the bottom of the garden, and attached it to our paving instead, Next she demanded we remove a small electrical box attached to the wall which houses the garage door electrics, which we did, placing it on a stand alone steel plate. However, she has written again saying we have not complied with her wishes which is nonsense. We are at our wits end and are losing patience, Can I legally attach things to the wall or not? I want to either be in the right, or if I absolutely must, build another wall beside hers.