I'll start with the thing a sales page won't tell you: most of the carpet in your house doesn't need a sanitizer.
A good cleaning already removes most of what people worry about. Soil, dander, crumbs, the film from spills, the residue from old shampoo. Our antibacterial sanitizer is an add-on that goes down after the carpet has been cleaned, aimed at bacteria, fungi and viruses sitting in the fiber. It's useful in some rooms and a waste of money in others. Here's how I'd split it up, walking through a typical house.
The nursery or playroom
Worth it. This is the clearest yes in the house.
Babies spend their days with their face a few inches off the carpet, and anything that hits the floor goes in a mouth eventually. Spit-up, milk, diaper leaks and teething crackers all end up in the pile. A cleaning lifts the residue. The sanitizer treats what's left in the fiber after that, which is the part a parent tends to think about at 2 a.m. while someone crawls across the rug. Wait until the carpet is dry before the baby goes back on it.
The bedroom where someone was sick
Also worth it, with timing in mind. After a stomach bug or a week of somebody coughing in bed, people want the room reset. A cleaning followed by the sanitizer is a sensible way to do that, along with washing the bedding and wiping down the hard surfaces. Book it once the illness has actually run its course; doing it while someone is still sick in the room means doing it twice.
I want to be careful here. A sanitizer treats the carpet. It doesn't treat people, and it's not going to stop the next cold from going around a house with three school-age kids in Pearland ISD. It just means the carpet isn't holding onto whatever was spilled on it during the bad week.
Where the pets sleep
It depends on what the problem is.
If the issue is urine, the sanitizer is the wrong tool. Urine soaks past the backing into the pad, and what fixes that is the live enzyme in our pet urine treatment, which reaches the pad and breaks the urine down. Sanitizing the surface over an untreated urine spot leaves the smell exactly where it was.
If the issue is the general dog-bed corner (drool, the occasional bit of vomit, a patch of carpet a dog has slept on every night for two years), then a cleaning plus sanitizer on that one area makes sense. It's a small spot, so it's a small cost.
The living room
Usually skip it. The living room gets the most traffic and the most soil, and that's a cleaning problem. A regular cleaning handles it. The exception is if a toddler spends most of the day on that carpet, in which case treat it like the playroom.
Hallways, stairs and the formal dining room
Skip. Hallways and stairs see shoes and feet, which means soil and grit. A sanitizer doesn't do anything for traffic lanes. The formal dining room that gets used at Thanksgiving and not much else doesn't need it either. Spend that money on cleaning more often.
The sofa
Sometimes. Upholstery collects body oils, food and whatever the kids were holding, and it's the one soft surface in the house that people put their face on. After an illness, or if the couch doubles as a sickbed, a sanitizer after upholstery cleaning is reasonable. A sofa that's just a bit grubby needs cleaning and nothing more.
A word on the climate
Pearland's damp air keeps carpet slower to dry and friendlier to anything that likes moisture. That's a real reason to care about how wet your carpet gets during cleaning, and it's one of the reasons our process uses very little water and the floor is typically walkable the same afternoon. It's less of a reason to sanitize every room. Dry carpet with no residue in it is already a poor place for things to grow.
How it fits into a visit
When the technician walks the rooms with you before starting, say which areas you want sanitized. They'll clean everything first, then apply the sanitizer only where you asked, and give you the price for both before any work begins. If you're unsure about a room, ask them. A good technician will tell you when a room doesn't need it.
If I had to pick one room in your house for this, it would be wherever the youngest person in the family spends the most time on the floor. Start there, live with it for a few months, and decide about the other rooms later.