You stated its for maintenance. Then all you need is a rake with gauge wheels to comb the surface, pull up some filler material and level it into ruts, chop down bumps and give it a crown.
Just tow the rake with weights on it. Let it float so that the gauge wheel set the surface flatness by what they are running on. If you can rig up a 2 pt attachment on the front or rear, then rotating the rake at 30 - 45 degree yaw angle with the rake's hitch pin also at an angle from the vertical, a crown will be formed. You can push the rake from a front frame mount or pull it from a rear mount. The 45 degree yaw angle also chops down the hills and depressions formed by
rigidly mounted blades, scrapers and tillers.
If the gravel or crushed asphalt is already in place and all it needs is a trimming. This is all you really need. Mine is 8' so when angled it easily covers the tire tracks. High angle, 1 pass down each side, then yaw angle of zero and a run down the center.
Done. No need for a $4000 occasional use special purpose machine. Heck, I use my JD suitcase weights on it and do my 1 mile long entire gravel road. But, the 'nice' roadway allows my neighbors to drive twice the speed limit, so I leave some occasional speed bumps by lifting the rake once in a while.
If your driveway is really bad and needs more than this, use a rototiller in the spring to loosen up the gravel. If you really have a rock driveway, put down some gravel, then grade it with the rake.
Now I don't need the rake any more because I put down 700' of concrete and the road now has to be done by the county.