I am the construction foreman for a local LC, we are putting in a 1500 sq. ft. patio with a circle kit out on one corner and a 2 ft. high sitting wall around the whole deal. I have done several paver jobs and even more walls but always seem to spend what seems like too time on the base. Also tips for setting the first course of block would be cool, my boss does not allow any stone dust to aid in leveling the course. Before working here I had always been told up to 3/8 of an inch was acceptable.