Beach cottages have small bathrooms and toilets that get heavy use, so when something goes wrong, you'll usually hear it. If the tank refills in an empty house, a flapper is letting water through all the time, and it adds up on the bill. If it keeps running after a flush, the fill valve is often worn out. If the toilet rocks at the base, the mounting is often loose and the wax seal beneath may fail next. In a beach home where the floors already deal with plenty of moisture, a failed seal only adds more water to the problem. Water already at the base means the seal has failed.
Repair usually comes first at the beach too. Tank parts can be replaced one at a time, a sound toilet keeps working with new parts, and corroded metal fittings can be replaced along the way. Replacement makes sense when the porcelain is cracked, when repair costs keep stacking up on a worn out toilet, or when you want an upgrade, since modern toilets can use far less water, which matters in a beach town, and a bidet can be added with any replacement. The recommendation is based on the toilet the contractor sees, and it's explained in plain English before any work starts.
It helps to know that a toilet backing up again and again usually points to a drain problem, and the drain has its own service and page. Running toilets, rocking bowls, leaks, seals and replacements are all performed by or under a licensed contractor, with the work suited to the small bathrooms beach cottages actually have. You get straight answers, and the decisions are yours.