3.Cheap machines have no safety caps when refilling water, versus safety caps. 4.The ability to refill water continuously is more important than you might think. 5.Holding water tank capacity. Very small water tanks can drive you crazy when you have to refill them every 15 to 20 minutes. 6.Having the ability to regulate the steam outflow with pressostat is important.
Some tasks require a finer more concentrated jet of steam.
This can be important when you want to avoid the splattering of dirt particulates all over the place. 7.Ability to regulate the steam temperature. Some fabrics and surfaces require a cooler temperature. 8.Length of warranty on boiler and other parts. It is usually 3 years on a good residential machine and 5 years on a commercial machine.