What should be the Limit of Private Ownership?

My Question for everyone is what aspects of life, roads, police, construction etc, should strictly remain under the control of the government? After all the organizations like the DEA and ATF have been burnt to the ground, which are the ones you give a pat on the back and tell them to keep up the good work? My main question here is just to find out what you think the limit of of Private ownership should be.