Best Smoke Detector Installation in Tampa FL

We've used Cornerstone for a number of years now but will not be calling them back.  We have a warranty on our ac for parts but the charge for labor has skyrocketed.  Our last bill was $799 dollars for just a couple of hours of labor.  When I called the office to ask what the hourly charge is, she told me it was up to the technician.  Then she said she would have someone get back with me, that was three days ago and still no phone call.  All I can say is Goodbye Cornerstone