Assuming the Exterior is completely dried in, the next steps to finish the project would be:Drywall or Wall Finish - a Cabin in Montana might prefer a Wood Finish instead of the Drywall we typically use in Arizona - Possibly a combination of both; I suspect Drywall would be least expensive but maybe not as Aesthetically correct.Assume an inspection is required to confirm proper Nailing of Wallboard prior to next steps - Make sure Wiring and Plumbing passed inspection prior to installing Wallboard.Tape, Texture, and Paint - If Drywall is used, not required for a Wood Wall Finish, but Wood might need to be Stained and Sealed.Flooring - Carpet, Tile, WoodMillwork - Cabinets and CountertopsElectrical Trim - Includes installation of Electrical Outlets, Switches, and Light Fixtures. 

He checked outlets, opened the fuse boxes and looked at the wiring, checked into the TINY attic, etc.

I haven’t had the pleasure of using them myself yet, but I’ve heard really good thing about the Appliance Repair Outlet in Snohomish.

Check this little creative method out: let's say person A and person B approach your rehab/construction business needing rehab.

The owner I’ve been communicating with no longer gets back to me, and I now have a new outlet with the other owner.

This plumber came in and installed washer and dryer outlets and moved the main lines for the water heaters.

You could also get a W2 and be more traditional... but if you're anything like me you don't want to wait for all that to sort out. Let's

Make sure doors, windows, outlets etc. are roughed in properly for this as well

Outlet covers everywhere, some of them you get close to, the hair on your arm stands on end.

Most of these items are small like replacing broken water shutoff valves, replacing some broken outlets, adding GFCI outlets where necessary, replace broken smoke detectors, etc.