I plan on literally starting with an action figure. I'm not really good with my hands and don't really know what I'm doing. And with how long it takes me to do anything, I'm probably decades away from something that'd probably make me happy. Not to mention that I just can't learn to code no matter how many times I've tried, so I'd have to get money before I could pay to have an AI made. The best I could do on my own would mostly just amount to a glorified mannequin/puppet. I guess on the Human-Mecha scale, I'd be starting at 4, then gradually working up to 1. Anything that I can't get looking and moving realistically (mechanically, not because of the programming) within realistic human body proportions, will instead look overtly mechanical. And as I mentioned in another thread, the brain will be a server rack and the body will be remotely controlled.
As far as the action figure goes, right now I'm just trying to figure out how to make something with a realistic or somewhat idealized range of motion with as few parts as possible. I keep trying to figure out how to make a near 180° bend at the knee without a double-hinge.