I've been using sand in my runs since I started in chickens about five years ago. In the last few months, I switched my coops from shavings to sand and love it! Everything I read said to use natural, washed sand and not manufactured sand which we have around here with all the granite quarries. I ended up buying bags of washed natural sand from Home Depot. It would be much cheaper in bulk but it's also easier to haul around a 50# bag instead of trying to move a pile bucket by bucket into my coops.
Clean up is easy with a kitty litter scoop. I toss in some powdered lime from time to time, mixing it well into the sand. It's nice not to have to clean out everything like I did with shavings or have shavings everywhere in the runs. I do keep my next boxes full of shavings but figured the coop needed something to function as litter and not bedding.