We've had it done before, it looked a lot better. Time wise was probably 1-2 hours, about the same time as cleaning carpet for example. In terms of staying off the tile, no time, more or less until the water dries. Be prepared that they will likely try to upsell you for sealing the grout, give a lecture about how if you don't pay for it that the grout will immediately get dirty again. You can get grout sealant from Lowes/Home Depot and do it yourself for pennies of what they charge. Its easy to do yourself.
@Katzen: Thanks, yes those floor cleaning companies always try to sell you on upcharges. Â Thanks for the advice.
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