I have done this is in inner city North Philadelphia. For those who are not familiar, North Philadelphia is a very challenging part of the city.. poverty, drugs, you name it.
For two years, we did a clean a thon for charity. Instead of a walk/run for charity, we pledged to clean as many vacant lots as our pledges.
First we go into a rough rough area. For the suburbanites, it was an eye opening experience. We did have "local" escorts from the local ODAAT chapter, and the health clinic (the cause we were supporting). These "escorts" walked us to the neighborhood, and we got to work. We saw lots of needles, and other things. We had to wear two sets of rubber gloves and then work gloves (the canvas kind) over the rubber gloves. It was wonderful cleaning the lots...
There was so much work to do , but it was wonderful work. First the locals were wondering what we were doing.. we were out there singing deep gospel music, raking, hoeing, and clearing out trash. (I can't tell you how many colt 45 bottles we found). Then as the lots were getting cleared, they would come by and say "Praise Jesus". and "Thank You". It was wonderful to see this neighborhood reaction.
First it was scary getting started, we did get jeers from the locals, and from others. As soon as they saw the local "escorts", they were much more accommodating.
I have to tell you about what we saw. So many beer/liquor bottles, needles, crack vials. The funniest thing happened though, I was raking away and found a $1 bill. Then I figured I would give that to the charity. I then said jokingly to the sky "OK, God give me a $20!" THen I start raking again in the same spot, what do I find... a $20 bill!

That went into the charity envelope!