Some interesting stuff in this FAA permit application.

The Grasshopper RLV consists of a Falcon 9 Stage 1 tank, a Merlin-1D engine, four steel landing legs, and a steel support structure. Carbon overwrapped pressure vessels (COPVs), which are filled with either nitrogen or helium, are attached to the support structure. The Merlin-1D engine has a maximum thrust of 122,000 pounds. The overall height of the Grasshopper RLV is 106 feet, and the tank height is 85 feet.

The propellants used in the Grasshopper RLV include a highly refined kerosene fuel, called RP-1, and liquid oxygen (LOX) as the oxidizer. The Grasshopper RLV has a maximum operational propellant load of approximately 6,900 gallons; however, the propellant loads for any one test would often be lower than the maximum propellant load. Even when the maximum propellant load is used, the majority of the propellant would remain unburned and would serve as ballast to keep the thrust-to-weight ratio low.

Back in the day, Phil Bono had designs for recoverable Saturn V upper stages that would land vertically on the ground.