Out here the bathroom count runs higher and the toilets work harder, with the main house, guest quarters and the bathroom off the barn or the workshop, and every toilet on the property shows the same signs when something's wrong. If a tank refills by itself, it's usually a flapper leak, and on a property watching its water, whether municipal or well, a leak running all year adds up to a lot of gallons. If it keeps running after a flush, the fill valve is often worn out. If the toilet rocks at the base, the mounting bolts are often loose and the wax seal may fail next, and the floors in older ranch homes are worth protecting from that kind of leak.
Repair does most of this work. Tank parts can be replaced one at a time, sound toilets keep going with new parts, and on a property with several bathrooms, keeping every toilet maintained usually costs less than replacing them one by one. Replacement makes sense when the porcelain is cracked, when the same toilet keeps needing repairs, or for the water savings. Out here those savings are real, since modern units flush on a fraction of what the old ones use, and that adds up across a property's toilets and a well system's budget. A bidet can be added to any replacement wherever you want one.
It also helps to know that a toilet backing up again and again usually points to a drain or septic line problem, which has its own service and page, and on septic that difference matters even more. The toilet's own work is performed by or under a licensed contractor. Everything is explained plainly, and you decide at your own pace. Every bathroom on the property gets the same careful work.