This can be tricky. I do free estimates for smaller jobs, one that I could put a bid together in a half day or less, but if it's a job that requires a "design", i.e. whole home, dedicated theater etc. I charge for the design time and request a $500 deposit. At the end of the design they get the paperwork and they can go elsewhere with it if they wish or they can continue with us and get a break on the final cost equalling the amount of the design cost, (which is factored in anyway).

The bottom line is - if someone wants a system designed for free that may take you a considerable amount of time then they are not appreciating the work you do and may not be your best customer anyway. I've lost jobs on this arguement before and couldn't care less. I need to know that my customers are good people to work with and are willing to invest some trust and cash in me to get the right system.