An auto-powered mobile machine with controls for a riding operator and a system for carrying and making efficient use of a variety of attachable tools. Most of the tools operate in a linear fashion and are most effective when held to one side of the machine with respect to its direction of movement. The machine includes wheels or tracks, a mounting base for attaching a controllable tool and, above the mounting base, a swivel on which sits an operator's seat and controls. An articulating arm is attached above the swivel so the operator may operate in a coordinated way a lower tool which does not swivel and an upper tool which does swivel to accomplish a job more efficiently than it could be accomplished using tools separately mounted one at a time. Wireless radio communication from the controls to the lower tool may allow the swivel to spin any number of times without limitation. A tool mounting base, which may also be an earth moving blade, moves vertically up and down staying plumb rather than pivoting and not remaining plumb. Hydraulic tool position controls respond to a string datum line, a curb, or GPS data. The system is completed by a variety of tool attachments, including a novel fence installer.