How do you know it is a scam?

We finally gave in...the rugs look worse, They used 877-780-7014 on invoice.

I had signed up for an appointment 11/2.  Got a reminder voice message with the same 650 632-0728 call back.  Tried twice..no reply yet.  No identifier on their answering system either so was questioning if I got the number right until I saw all your inputs.  Will be interesting when they show up tomorrow and I'm not here.

They did show up 11/2 not out of the SF office but out of Santa Clara.  The two young guys apologized stating no one answers the 800 number on the weekends.  The gave me a card:  Rug Steamer, Professional Carpet & Upholstery, (888) 298-7279.  Hand wrote another number on back (415) 632-0728.  May help others.

Careful, these people don't seem to be real professionals, probably illegals. They will not show ids and the cards don't match the name of the calling company.