Just so you know, I've lived on private roads for a long time (all three houses I've owned and lived in since 1992). The first two we maintained ourselves, since we were the only property actually using those roads while we lived in those houses. Where we are now, there are 11 properties on the road. Most owners do cut back the brush in front of their properties periodically, but two single-women owners have trouble keeping up with theirs so we have occasional road "work parties" where the guys with chainsaws clean up brush, leaning saplings, broken branches, etc. and everyone helps fill potholes and rake out washboards.
My county has rules for taking over private roads. They boil down to (1) the road must serve at least 5 properties and (2) it must be built to their standards when you apply to turn it over to them. Your city (are you inside the city limits?) probably has rules of its own that you can ask about.