If you have a Scope Buggy (or similar) these work great.? After leveling and getting wheels off the ground, just leave the jacks in place.? Solid.? Low Cost.? Perfect.
George
Labor Saving Arm Tool Jack, 2 Packs Effort Elevator Handheld Lift, Wall Tile Locator, Door Panel Lift, Washing Machine Leveling, Precise Control Slow Descent, 260lbs Lift Capacity?