I built the PiDP-11 during Covid when stuck at home. I had basically zero soldering experience so I bought a $10 soldering practice kit online first, but other than that it's doable by anyone. It was super fun. I had to take it apart later when I had a set of LEDs that wouldn't work and poked around until I found a solder I had messed up. That was also fun. It sits in my office running blinkenlights most of the time these days - anyway would recommend buying one of these kits!

Edit: I'd guess it took about 6 hours for me to finish over the course of several days, if you are good at soldering it will be cheaper. I stopped a lot to double check stuff like polarity on the LEDs (I think it was LEDs) and what-not.