Both their functionings are complex, so people can get impressed. But for both of them, all the complexity is inside the device and there isn’t much to put together; and the way they hook up to your house is really simple.
Why YSK: so you don’t live too long with a broken toilet or garbage disposal, thinking it will be too hard to replace. Those two are some of the simplest things to DIY.
I was really apprehensive about working on some toilet repairs (replacing everything inside the tank). I bought a kit from Home Depot and it was basically like a giant game of adult LEGOs, complete with an illustrated instruction book. Annoyingly, I had to cut all of the existing bolts, which was difficult, and the kit only came with 2 bolts instead of the 3 I needed, but other than that, it’s not rocket surgery.