Drains in seasonally used homes have their own habits, and in a villa they are shared with the neighbours.
Traps dry out in empty homes
Water sitting in a drain trap evaporates when a house stands unused, and once it does there is nothing sealing the drain, so odour comes back into the room. It is very often mistaken for a serious fault when the answer is running the taps for a minute in every unused bathroom.
Shared lines in villas
Where several homes feed one line, a blockage may have nothing to do with your unit. If neighbours are having similar trouble, that is useful information rather than coincidence, and scheduled clearing for the building costs far less than repeated individual call-outs.
Sand from the beach
Sand is heavy and settles in traps and low spots rather than washing through. Jetting removes it properly where a cable would only make a channel.
Heavy use in short bursts
A house that sleeps eight does a month of ordinary use in a long weekend, and lines that seemed fine can block under that load.