Call the State Contractors License Board (800-321-2752) and check the License status, (i.e. up to date bond standing in effect) or any red flags. Contact the Better Business Bureau for information about the builder's reputation. (714-527-0860 then enter 909-595-1215) Check for consistency in equipment product line & ask for exact equipment brochures. Make sure you purchase what is correct for your project. Your builder should consider performance curves, lengths of runs, total dynamic head pressure & pool shape for your particular application. Location of return lines and skimmer placement, if done improperly will cause years of problems and innefficiency. Pool companies that use brand X for the pump, brand Y for the motor, brand Z for the heater, may be buying the cheapest individual items from wholesalers without concern for you or the project's maximum efficiency. They are only considering their costs. Top of the line equipment engineered to be compatible with one another will give you the best overall service and performance. No Generic Brands Visit the place of business. Some companies don't even have a business address. Meet the support staff, observe office procedures and appearance. If they look unprofessional and out of sorts there, how will they perform at your home?