In an ideal situation, Gov should be like a headman = Nyapara. He should find the highest point at a labor camp and stand on it looking down as the workers do their job. The workers in this case are Private companies, State owned companies with no special privileges, County owned companies, NGOs as we know them, Individuals, etc. The Gov should identify areas it wants interventions and then float tenders and offer incentives. It should fairly select the best offers / bids and supervise the implementation either directly or through a tendered consultancy.
There is no limit. I once had a useless argument with PK over garbage in which I pointed out that nobody needs pay to dispose of garbage but that Counties should get paid for allowing somebody to collect garbage. A few weeks or months later we started seeing contracts "similar to what Omollo suggested.." being signed left right and center. I say the same: We do not need to pay anybody to build a road! They should pay us to allow them to build the road! This is applicable to all manner of infrastructural projects - sewage, drainage, hospitals, name it! I can explain the principle if need be but suffice to say, a well constructed road lasting 100 years can have a meter showing the traffic and attract the same amount from the fuel levy to be paid to the investor. This is easier than operating a toll station.
I think in the future we need to define what gov service really are. Right now gov all over the world basically can do everything or nothing.