RV Boondocking on city streets - where is it legal?

What that means is that I can walk onto your porch and knock on your door. I am not trespassing. If you tell me to leave and I delay or refuse then I am trespassing. If I am in a building I am trespassing. The simple act of merely being present on your property is not LEGAL trespassing. Morally if I am some place that you have legal control over, yes in your mind I fit the description of a trespasser, but more than likely will not rise to the legal definition. The law is a funny thing!