I do not think this is the right way to respond to possible or potential customers to your offer. He just might be interested in your offer but would need to get things clear with you so as to get more knowledge on what your offer is all about. Your response to him or her sounds rude though but it would have been better you had inquired to know   more in his interest because this would have added more knowledge to you too to either noting some errors and fixing it up and as well having more features on your services you render. This you should know that no man is an island. Everybody has his or her ways too. He just might give you more tips on adding more attractive value to your offer but your approach to him is not welcoming in anyway