This type of scam artist is unlicensed, uninsured, and probably lacking in experience. He may use high pressure or scare tactics, and “bonus offers” to get your business. He may ask you for a substantial down payment prior to starting the job. Beware of any and all such schemes.
If you do use an unlicensed, uninsured firm or individual, don’t be mislead into believing that your homeowner’s or personal liability policy necessarily protects you. In many cases, you may be liable for suit.
A large number of home and building owners have been dragged into litigation involving uninsured contractors. If an employee of an unlicensed contractor is injured on your home or building, you may be responsible for his injuries or disabilities. In addition, you probably have no protection in the event damage is done to your property or the property of others by the roofer during the course of the work.
Often the end result of using an unlicensed contractor is a poorly installed or poorly designed roofing system. This is worse than no job at all, and may end up costing you more in the long run.
Another reason to avoid this type of contractor: if he does not pay the suppliers whose materials are used on your project, you may find a lien placed on your property even though you have paid for the work. This means you may end up paying for the same materials twice.
All in all, most home and building owners have found that using unlicensed, uninsured roofers is not worth the risk.
Source: Colorado Roofing Association