CHECK A CONTRACTORS LICENSE (CSLB)=Contractors State License Bureau..

1: If a vendor claims that has a Contractors License, ask them to provide the number and then verify it on a website below or 
    at CLSB LICENCE CHECK to make sure the license is current.Normally the number will have 6 or 7 digits.
2: If you cannot find it let  the vendor know to send you a copy of their license or to check the name again as you could not find it on the contractors
     state website. It is possible they get  you the City Business License # which anyone can obtain for less than $200.
3: The City of San Diego Business tax license can be checked by name at BUSINESS LICENSE