Most carpet cleaners will advertise the fact that they have truck-mounted carpet cleaning machines, and there is a very good reason for this.
Truck mounted carpet cleaning provides superior cleaning.
Many carpet cleaners will say that using any other method is just not cleaning the carpet.
If the machines the carpet cleaners use are not powerful enough, all of the soap and dirt will not come out of the carpet.
If the soap stays in the carpet this posses special issues. Soap has a magnetic attraction. If soap is left in your carpet, it will attract dirt to that specific area. This will cause your carpet to look dirtier than before the carpet cleaners even cleaned your carpet.
Powerful truck mounted machines are huge, so large they are mounted permanently on the truck/ vans (hence the name).
Inside these large machines they get the water scorching hot to kill the bacteria, and they have powerful vacuums that remove the soap and dirt from the carpet.
Truck-mounted carpet cleaning is what you should insist on when hiring a carpet cleaning professional. Anything less, and you really could do it yourself with a store bought machine.
