He's building it in a shed. With scraps. That he bought... on eBay.
The Hulkbuster suit from Age of UltronImage: Marvel Studios
At one point in this video, the second in a series in which Colin Furze works to create a life-sized replica of the Hulkbuster armour from the Marvel Cinematic Universe (specifically the Infinity War version), the creator pauses and says, "This is the most complicated thing I've ever worked on." And you can tell; with hydraulic pumps, metal work and incredible engineering, Furze is building a moving Hulkbuster one limb at a time.
In the video posted this week, he puts together the torso, arms, and hips, which move due to the aforementioned hydraulics and other things that I, as someone who failed the mechanical portion of an aptitude test in high school, do not understand.
Before this, Furze has built some other incredible replicas, including a full-size TIE Silencer and an AT-AT. But this, when it's finished, might be his masterpiece.
Looking forward to the reveal video.