This POC shows that a common device called a "Pump Jack" can be used to provide fulcrum positions for a Lifter. I modified them so that they would fit under the Carriage. When the Carriage is tilted one Pump Jack slides up the Vertical Support as the other one supports the Carriage.
Lifter with Pump Jacks resting
Lifter with Pump Jacks (top)
Lifter being Tilted
My Son and I show just how easy it is for two adults to operate the Lifter. The Vertical Support is 20 ft high and the Carriage and its payload weighs around 570 lbs. ( probably closer to 550 lbs. 14 Blocks x 33 lbs + the pump jacks and the Carriage Assembly ) We tilted it up to almost 9 feet.