Can you use a carpet cleaner on vinyl or laminate floors?

Only with care, and usually it is the wrong tool. Luxury vinyl plank and sheet vinyl are sealed and tolerate damp, but a carpet cleaner is designed to put solution down and pull it back out of pile, and on a flat surface it tends to leave standing water at the edges and seams. If your machine's manual lists an approved hard floor tool, use that on a low solution setting and dry the floor straight away; otherwise use a wet dry floor washer or a damp mop.

It is best avoided. Laminate has a fibreboard core under its wear layer, and water that gets into a seam makes that core swell and peak permanently, which no amount of drying undoes. Laminate makers' care guides warn against standing water and wet mopping, so a vacuum or cordless stick for grit and a barely damp mop for film is the safer routine.

You can, but it is working against its design. Soft roller or suction only. Sealed surfaces tolerate damp but not standing water. It is not a vacuum. You still vacuum first, every time. If this floor is most of your home, the table above shows what owners of this surface more often settle on, and the difference is usually obvious within a week.

Soaking a laminate seam, which swells the core permanently. That is the failure that is hard to undo, as opposed to a machine simply underperforming. The rest is a matter of degree: a less suitable vacuum leaves the floor less clean, while the wrong technique on this surface can leave marks or damage that no amount of cleaning afterwards fixes.

Less than people expect, on any floor. Sealed suction figures are measured with the inlet blocked, which is not a condition you ever clean in. What decides the result is airflow through an unblocked path, the head design, and on carpet the agitation from a driven brush roll. Compare like against like within a machine type and treat headline figures as marketing.

Usually not, and most homes are better served by one capable machine with an adjustable head than by two specialised ones. The exception is a home split roughly evenly between deep pile carpet and sealed hard floor, where the requirements genuinely conflict, and a second machine or a separate floor washer starts to earn its place.

Grit is what wears a floor, so frequency matters more than power on hard surfaces, where a light pass every few days does more good than a thorough one every fortnight. On carpet the reverse holds: the dirt sits down in the pile and only comes out with slow, overlapping passes, so fewer but more careful sessions beat frequent quick ones.