Always visit commercials to quote, otherwise, yes you may get caught out. You need to see the job. Assuming its low profile you should be able to encap with a rotary/cimex and get very good results. Carpet is around 18m by 18m, so its a small job to do in reality...... vinyl, a good scrub brush/pad and a good floor cleaner and a piece of p........ If really heavy soiling on carpet you may need to do a few areas with hwe, and make sure you have a product that deals well with coffee................ price wise i tend to look at these jobs, estimate how long it will take, how much i want to earn in a day, how much the chems will cost and work it from there......