Below is the machine I have used for 15 years. Connect shop air hose for air supply, controls are battery powered, recharge once a month, very low operating cost. Filtering isn’t very fast, there is a 60-gallon reservoir tank on the back of the machine. Connect hoses to all four tires, set the pressure and walk away, tires are purged, inflated, purged again and inflated to the selected pressure.
A shop I worked at in the past had a liquefied nitrogen tank, refilled once each week, I believe it was refilled by the same truck that services bars and restaurants.