First, get a glazed trap.
That's the crucial S-curve below the toilet bowl.
How do you know it is glazed? You put your hand down the new, dry, clean unused toilet and feel below the bowl! Is it rough ,,, or smooth as the bowl?
Why is this so important? Because unglazed toilet bowl "traps" will clog up much More often than glazed ones. Yes, even Home Depot tries to fob-off unglazed toilet trap toilets, so beware !!
Second, get the Widest trap you can find, as there is a big difference brand to brand, of even an inch or half an inch. Same reason,,, do you want to be toilet plungering and snaking and mopping,,, or not ,,, weekly or daily ?
Third, get the Adult size toilet and a good brand like Gerber,,, not a child's/"family" 2 inch lower toilet. Have your kids use a short wide step. Ask any gerontologist MD worth a crap and they will say "adult size" for adults,,,
Fourth, shop around.
Usually the cheap Glacier and Kolher are out front.
Ask, "Where do you hide the better brands, like Gerber?"
Try a pro installer store, if you are brave and smart enough, like R.V. Cloud in SillyCon Valley. I got a few of the last 1.6 cu ft flush Gerbers, in the far back warehouse before the nuisance Feds banned them;They should have banned unglazed traps! but didn't do the smart thing, as usual.
Fifth, buy oval rim toilet bowls, not round rim ones, unless you want men peeing down the front and on your floor. All the time. Think about it.
Sixth, use a good flexible hose with woven metal mesh outside to connect to the water supply, not some cheap rigid jointed metal pipe, Especially in earthquake country, like the Pacific Rim.
Seventh, if you poop big try double flushing the poop first and then the TP.
If your are still worried about plugging a toilet, squirt some dish soap, left in the bathroom, just inside
the rim.
Eight, you may have tree roots growing in your house to street drain/sewer line, slowing the flow. Find out where all your kitchen sink and bathroom drains go and have them snaked annually or biannually but at least every 3 years. Remember plumber snakes can not go thru a 90 degree turn, so if you have only one cleaning access you might have never really had your house line cleared out or snaked all the way to the street sewer. And don't trust most plumbers to tell you if you do have a 90 degree drain problem as my parents were lied to for over 40 years by many plumbers who promised they had snaked "all the way to the street" and charged extra for it,but in truth never got past the 90 degree drain turn on the far side of the house. We eventually found a very rare honest plumber and we dug the hole and he put the second cleaning access in and for the very first time cleaned the house drain all the way to the street sewer line!!
Beware of overflowing toilets wetting and rotting the cross-direction 2 subfloors, as that is an expensive repair.
Beware any plumber who say "The subfloor is totally rotted and the thick metal circular mounting flange has turned to flakes of rust, so I'm just going to screw,,, a thin cheap metal flange on top of the totally rusted thick one and leave it like that." Quickly escort that Fool out of your house or condo or apt.!!
Beware of any plumber or tradesperson or "handyman" who shows up with a dirty messy truck with dirty uncared for tools and a pile of parts; in fact ,ask to look at his truck and tools First! and if his tools are clean and well cared for and his truck is organized, only Then would I let him ,with bootie covers, into My home!!
This is some of the basics.
I hope it helps.
If you are too ignorant and or stubborn to take good free advice,,,
