That's a tough one...
I don't engage with homeless people. I had a guy sponge $10 off of me, he said his car was broken down. I said I would drive him back and he said he needed more money. This was outside my bank on a Friday, right after I got paid. (I actually WORK......) So I ask what kind of car it is?, and I go to look for it, no car. I drive back to the bank, of course, he's long gone. I did catch him 2 years later getting off of a bus in another city, and I went up to him and confronted him, uh rather forcefully in front of my son.
Of course he was broke, didn't have my money, and I scared the holy sh*t out of him. My son thought I was a tough guy.
So, I don't engage.
At all.