I usually show them an app that does most of if not all of what they are describing. Or will say I am just too focused on what I have going now to add another

I usually show them an app that does most of if not all of what they are describing. Or will say I am just too focused on what I have going now to add another thing to the list. I have also used the same basic idea of "I don't have enough time right now, but if you have customers lined up already or can get them and show me that a real business opportunity exists I am happy to look more into it." Generally, I try to be polite about it overall and I don't dismiss people or their ideas outright, I listen politely and then judge based on merits (exception would be drunk cousin Eddie who won't remember in the morning so I just walk away).