Drains & Vents in studio addition

[AKAJIMSTER]

I am adding plumbing to a room above our garage and laundry room to be able to rent out as a one room studio. The main lines & branches have already been run by a handyman/plumber friend of a friend and I've got a few concerns about the layout and whether or not I'll have problems with the venting or who knows what else. I know I definitely need to add a cleanout; don't know where the best spot for that would be either. Forget about asking the inspector to have it inspected; I tried the legal route first(getting a permit). Every time I went down to the city to double check requirements, etc., the price went up as did the requirements, which had nothing to do with the plumbing. I've attempted a diagram and looking for feedback and suggestions for improvement. Thanks in advance.