Residential Concrete Structural Engineer Needed

I am planning to pour a 5 inch concrete slab that has two sections (two rectangles touching/continuous pour). One is 12x30 basic patio, and the other is 16x20 with foundation. They will be poured next to a 24 inch CMU wall with a manufactured home on it. I will be adding a 16x20 shed/building to one be side of it, with plumbing and electric. So I need a thickened edged slab and footing for the building. Are there different requirements and drawings needed if have the detached building is inches away from the MFG home, vs 6 feet away? How much for a drawing of the slab/foundation. Can you also do a drawing of the building structure? I can send the drawings that I did so you can get a sense of it. The drawings must meet local Show Low Arizona USA building codes and be able to pass permitting process.