Rewiring a home, upgrading a panel, and others - Quotes - Brainstorming Ideas

Hey All. Buying a home that has 2 wire.

Key details:

• 1951 home
• 670 Sqft.
• Single Level on Slab foundation.
• 100 Amp outside panel
• In Washington State, I can pull a permit myself to do the work.
• I've gotten quotes for just the rewire, $15k - $50K

Looking to:

• Rewire home so its properly grounded and up to 2023 NEC code.
• Upgrade to 200 or 400 amp service for garage + ADU's
• Update Panel
• Add 100 amp sub-panel to garage.

Key understanding of current code:

• 12/2 Romex for Bed, Bath, Kitchen, Living Room, Laundry with 20 Amp breakers
• 2 20amp circuits in Kitchen
• Dryer gets 10/3, 30 amp
• Range either 6/3 or 8/3
• Dedicated circuit for:
  • Microwave
  • Dishwasher
  • Garbage disposal
  • Fridge
  • Bathroom
  • Laundry
• Every 12ft on wall gets an outlet
• Wall larger than 2ft gets an outlet
• Every 4 feet on counters in kitchen
• AFCI and GFCI Protection, especially GFCI within 3 feet of water source and outside
• Properly bonding to panel
• 2.25 cu in for #12 wire for box fill requirements
• Staples within 8" of plastic, 12 if metal, then every 4.5 ft.
• 1.25" from stud edge
• 12/3 Romex for switches
• Fire foam for top plates
• Boxes mounted flush with drywall
• THHN/THWN-2 #3 copper or #1 aluminum for 100A subpanel

Questions:

1. As I will be pulling a permit and getting it properly inspected, would the liability be on me or the inspector?
2. If I were to fish the wire through the walls so they are at the outlet/fan/light/panel, would an electrician wire each end so its done correctly?
3. Does the Inspector need to see the full wire or just where its stapled and at each end? do I need to cut the drywall for the whole run?
4. Any tips that you might have?

Obviously wish I could have went to school to learn Electricity or have the $ to pay an electrician to do the whole job, unfortunately that isn't the case so will be looking to get this done myself.