We are converting a garage to a summer cabin. All the fresh water supply and the DWV will be along one wall. Everything will be within about 12-13 feet of each side of the pipe going to the septic system. The usual setup , dishwasher, kitchen sink, toilet, bathroom sink, shower and washer. Things will be pretty much in line with each other, along the wall. Right now we have a toilet connected directly to the drain to the septic (long story) we currently use it to drain the washer. We will be building the floor for this area 2 feet above the concrete slab. I'm looking for the simplest DWV system possible for this setup. Any ideas would be appreciated.
Thanks! :)

I'm looking for the simplest DWV system possible for this setup
The drawing ,(see image) is how the bath is laid out. The kitchen will connect to the main with its own vent witch may be revented back to the bathroom vent before it goes through the roof. More questions? I'm as close as a click. Good luck, Tom

Tom gave you one option, I will offer second one...
You are not saying what Code you fall under. I work under UPC. This is how I would plumb it...