By a city-wide eruv in chu”l, is one able to rely on sechiras reshus from a government official or any other similar position? Additionally, if one is relying on telephone wires as a koreh on lechi’s, is it a problem if the wires are sagging down or moving in the wind?
Regarding renting “place from the local officials, it is hard to answer you without knowing the specific powers that the local officials have. As far as the telephone lines are concerned, it depends on how they are made, and a number of other conditions, that the posts need, such as not getting blown in the wind etc. therefore it would be best for you to speak to the certifying Rov of that particular eruv.