Berkeley Humanoid Lite is an open-source, budget-friendly humanoid robot created by UC Berkeley researchers to make robotics research easier for everyone. It’s a customizable, 3D-printed robot designed for researchers, teachers, and hobbyists. Unlike expensive, closed-source commercial robots (often over $100,000), it costs less than $5,000 by using common parts and desktop 3D printers. The robot’s motors and body use 3D-printed cycloidal gearboxes, keeping costs low while staying sturdy. You can buy all parts from online stores, and the design works with a 3D printer that has at least a 200 x 200 x 200 mm build space. It’s 80 cm
Still hardware is expensive.
With the current tools i don’t think there is a specific hurdle. The biggest ones are funding and time.
You have to build expensive prototypes, learn from them and repeat that process till we are happy with the result.