I am a homeowner looking to install a 14x40 area using the precast flagstone(Uniform thickness & 5 piece pattern) from Lowe's. Had the base of compacted gravel set & compacted last fall. Now it is time for the installation(once the flagstone arrives). I would like some professional opinions about how to proceed. 1. Spread 1" base of sand. Should this be compacted of loose? I am hesitant to use tamper on flagstone for fear of breakage. 2. Should I use polymeric for joints or pea gravel? Combination of the 2? 3. Due to irregular shape is edge restraint needed? I figured it would at least keep the poly and/or pea gravel contained/separated from decorative rock that will be install around the flagstones. Appreciate any comments/suggestions on this.