First off guys I'm not a professional landscaper nor am I going to start in the business of it, mopwing keeps me too busy as it is (getting out of it soon) but I am helping my mother in law with a project. What she's got is about 450 sq ft. she wants to put creek rock in, and have a few plants and grasses in. She is a gardening whiz and she knows what she wants and how she wants it too look and basically all I am doing is helping her with the manual labor. With 450 sq. ft. I figured it would take 1 3/8 cubic yards of rock for every 1 inch thickness. She doesn't know exactly how thick she wants it, I kinda thought 3" is too thick and am probably thinking about 2" thickness is ideal. Yes there will be fabric laid underneath it. Next question, she has some larger creek stones (smallest is approx 2 sq ft up to 4 sq ft) 3-4" thick that she wants in there as stepping stones. Would it be better and easier to lay a sand base under where these are going or just let them rest on the dirt and place the rock around them. I'm thinking sand woudl be the way to go under them so that it is easier to level them and less likely to settle and be unlevel in a year or so.