I haven’t had any cleaned in a number of years after I changed everything over to hard surfaces. But yes the big van mounted guys do the best job IMO. Most of them offer a service to scotch guard after they clean and I recommend that. Reason being is I have seen firsthand how good that works to keep the dirt from working down into the carpet. It works different than you would first think as when you have it treated it gets dirty and needs cleaned again about twice as fast as if you didn’t have it treated. That is the dirt doesn’t seem to be able to work down in. so you will be cleaning more often but the results will really get the carpet clean.