Lessons you learned building your shop?

[Falcon67]

bobadame - can you point me to any step-by-step for how to do the site prep / build forms / place steel and mesh? i would LOVE to do that work myself and save the labor cost!

Go to your local P&Z or permit office and get the requirements. You can then look up similar items on the web or on here. There is no one way really - here it's slab-on-grade don't dig unless you have to, and in Alaska the footings may be 6' deep.

What my friend in the trade told me here: Don't dig squat, make your forms high enough to keep the floor at least 6" off grade, 8" better. Bring in fill later. 16" wide permeter footing for a stick build, sharpshooter shovel wide beams across at about 12 foot intervals, pack the sand to 4 1/2" and it'll settle to about 5", two runs 1/2" rebar on perimeter, 3/8 on 18" centers in the main floor. Watch craigslist and local equipment auctions for overstock rebar. Make damn sure the forms are level and well braced. AND - Let him bring his guys to work/finish because if one or two amateurs try to float and finish a 24x44 they WILL screw it up. He said I MIGHT get it in for $120/yd doing all the prep work DIY.
Just remember: foundation ***** = building *****. Better to have a nice slab and no building than cheat the start and suffer later.