Carpet cleaning business in the UK is dominated by one man bands. As in every aspect of cleaning business, a good cleaner need to have a combination of certain featuers: cleaning OCD plus good eye for details plus physical power. It is not easy job, there is no place for 'bad days' as effect needs to be perfect every time. Apart of individual features, a good machine, good products and training is needed as well. And here start an ongoing discussion about 'my hose is longer than yours...'
There is few types of carpet cleaning machines : ones professional laughs at like puzzi or rug doctor or bissett which have such low parameters that a simple household brush, bit of soap and wet van would do better. These machines are carpet cleaning professinals nightmare... and love. While they cheap to hire, they hold hidden charges like boosted chemicals cost and (client's) labour time. Effects are very poor, stains cannot be removed, there is no prespray, no agitation. That often leads to overwet, smelly, soiled carpets. And when the rug doctor client is fed up with recleaning and febreezing, they call professionals, and after seeing difference in service in equipment, they often stay with pros for good.
Another group of machines are professional portable machines: the power range and price range is very wide but even the weakest and cheapest ones are usually at least 5 times more powerful than cheap hire machines and they often have heaters to dissolve dirt. The way they function is more sophisticated, that is why they should be operated by experienced staff. The industry is full of professinal training and products providers. Machines spraying power is measured in psi and this can vary from 200psi up to even 1500 psi. However, for domestic carpets and upholsteries a range of 200-400psi is used, higher powers are used in hard floor cleaning. Those machines are mobile, can be moved inside buildings, even in difficult to access places. They need in house electricity.
Truck mount cleaning systems are large diesel powered machines mounted on the van, they use indpendent power system and ofer high power spray and suction. Unfortunately, they cannot be used everywhere as some works are not accessible from the van despite long hoses. Sometimes the hoses are also dirty due to being dragged outside a lot.
More important than equipment are other aspects: knowledge, experience, good chemicals, good preparation of carpets or fabrics, well built business structure including insurance, good reviews and testimonials.