I haven't dealt with this too much, but in my experience it's all in how you present yourself and your needs. If you're going to film in, say, Frank's house, Frank is going to want some details broken down so he can understand them. Details like, say, how many people will be involved? What happens if someone accidentally breaks that $2,000 vase he has on his mantle? (Two words: release form.)
Point is, even if it's a friend's house you should still treat it like a professional arrangement. Lay out on paper what you're doing, who is involved, how many hours you'll be there, what gear you'll be bringing, what you may need to change or alter while shooting there, and any other details that might be useful. And, get yourself a release form (there are templates all over the web; Google is our friend!) so that you aren't held responsible just in case your boom operator DOES knock over that $2,000 vase on Frank's mantle. Do everything you can to ensure the property owner that you will take extensive care of the property while you're on it and that when you leave, it will look exactly like it did when you arrived.
And then, of course, live up to what you promise. You never know, you might need to re-shoot later down the road.
This can apply to people you know or don't. Just be polite and professional, answer any questions honestly, and don't make promises you can't keep just to secure the location.
Hope that helps, anyway.