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.
There’s really only about 4 reasons to replace your whole toilet.
You don’t like how your toilet looks and want to get a prettier one.
Your toilet is physically cracked and broken, like if someone flushed a cherry bomb or took a hammer to it or something.
You have an old toilet and want one that’s more water efficient (and even then there may be a couple option you can use to work around it, like installing a dual flush valve, or sticking a brick or something in the tank to displace some of the water and see if it still flushes well enough)
Something else broke in your toilet and you have some weird, non-standard toilet that you absolutely cannot get parts for. For probably 90% of the toilets out there you can use whatever the hardware store carries that says it’s a universal fit and for most of the other 10% you can use one of the two things that are right there next to it on the shelf.
Other than than those reasons, you can go buy a kit to replace basically all of your toilets internal parts for like $25-$30 that will fix basically any other issue your likely having, for another $20-$30 you can replace the wax ring and flange if that’s what’s causing your issue, and that will account for about 99% of any issues you’re ever likely to have with your throne, and all you’ll need to do it is a screwdriver and a crescent wrench (and maybe some WD-40 or your penetrating oil of choice if you have some rusted up bolts)
In case anyone feels emboldened to fix their own toilet after reading that, for a few extra bucks you can upgrade to a dual flush valve that will fit most toilets and help you save a little water, and while you have everything apart anyway go ahead and install a bidet.
Yeah, I had to replace both my toilets, because they both cracked within 6 months of each other! Part of it is possibly that I’m quite unlucky, but part of it is also probably that they both just very old.
Definitely agreed that if your issue is not as fundamental and is something working weird in the tank for instance, the failing part is most likely easy and cheap to replace in isolation.