I too would just say "no, I don't lend out my patterns, (or any of my stuff)". Which is true for us here. We get asked to "borrow" the Dyson, or "borrow" the rug shampoo-er. We have learned to say "no, we don't lend out anything, and we don't borrow anything either". So far no one has gotten upset with that answer. It's the truth too.