Hi Superware,
I think its better to have a starting than to try get it right away the perfect way. When I started with OSM in Israel I remember how I added parts of the Highway 4 to the map. Of course without GPS tracks!
Today there are very accurate and every exit is defined even with the name [Talkat
]. In some areas there will be people defining the city borders very accurate in some areas nobody will touch it for years and it will stay not wrong.
My opinion: Better start something not accurate than not adding it at all to the map.
Of course I should add a note, saying its just guessing.
Regarding the government . Please try. Till today we didn’t get anything from the government. There are discussion threads with this topic here.