Seattle contractor prices are all across the board

I just bought a 1.12 million dollar house in Seattle and was looking for work to be done. Its crazy how much prices can differ from one contractor to the next. And how expensive some companies are. I think some people take a look at the house I got and get the idea I will pay any amount they can dream up.

Install L6-30R plug for car charger, 5 feet from the electrical panel.
Estimate 1: $750
Estimate 2: $4000
Estimate 3: $350

Install 3 electrical outlets, one in each upstairs bathroom
Estimate 1: $1500
Estimate 2: $500

Sand and refinish 10×10 section of floor
Estimate 1: $1000
This should be like $3 a square foot.

Refinish cabinets, stain sun faded cabinets:
Estimate 1: $8000

Painting, 3 rooms
Estimate 1: $650, I bought my own paint