So many times a company is licensed but in ONLY in one area. An example is they might have a CR21 License but you want them to do a BBQ, fire pit, property walls, retaining walls, etc. This license does NOT allow them to perform this work. Allowing them to do this work, they are in violation of their license. If anything does go array, then you have limited recourse to recoup any of your money. Buyer beware is a common phrase used when it comes to this. Please log on to https://roc.az.gov and search for that company. Here you will find any violations, suspensions, how long they have been licensed and what they can specially and legally contract for.