Rural cabin build: porta potty for 6 months until septic is in.

We're building a new cabin on a rural lot in Oregon, no utilities at all yet, and the septic system won't be installed for at least six months. There will be two to four of us working and staying on site most days, no food service or alcohol, just construction and basic living. The ground is uneven forest floor, but I can clear a spot and level it. A service truck can drive right up to the location. I'm looking at a standard portable toilet with a holding tank, but also considering a deluxe unit with a flushing bowl and sink or even a small restroom trailer if the cost makes sense for half a year. What's the most practical setup for a long-term rural build without power or water? Should I stick with a basic unit and add a separate handwash station, or is upgrading to a flushing model worth it for daily use?