4 tests, 4 different results-help!

[poolbee]

Took water to builder for testing:
FC 3.5
CC 0.1
pH 7.8
Cal 110
Alk 0 !!!(with stabilizer correction)
CYA 40
salt 3,000(used a device of some sort)

pool chain store:
FC 3
CC 0
pH 8.0
Cal 150
Alk 120
salt 4,800 !!!!!!(used salt test strip)

other pool builder

salt 3200-3300(they did salt strip test twice)
Alk 85
Cal 140

PS234s(me)
FC 5
CC 0
pH 7.8
Alk 100
Cal 170
CYA 45
salt 3200

My numbers are repeatable and have been pretty steady the past 2 weeks.

I realize I need to adjust my pH and that my calcium needs to be higher. My pool builder store sold me a bag of Cal Chloride 77% by "Flake" It has directions on it for melting ice and other uses but no pool directions.
Is this stuff Ok for the pool or should I get cal chloride specifically for the pool. I am having bad rust problems on the ladder and light. Could this be from the low calcium or bad bolts? The pool is only 1 month old.

My pool builder store also told me to add 35 lbs of baking soda. How do I know that since their numbers are so off from the rest? I realize again I need to up the Alk but by how much? No one else correct for CYA. Could it really be 0?

I was told by everyone to leave the CYA alone since my FC is fine and the lower the CYA the better. I have a SWG-AutoPilot, which recommends 60-80, but everyone said leave it. I was told CYA is banned in California. True?

My pool builder used a meter of some sort to do all the tests, chain store and other builder used drop tests and salt strip. I am assuming(hoping) the chain store guy misread the strip

Now my pool is clean and clear-and rusting.

Also, my builder gave me a computer printout with directions to add cal to water in pool. Tech hand wrote directions to mix Cal chlor in a bucket with water and then add to pool. Other pool builder and cal chlor bag say NEVER pre mix. I should assume tha manufacturer is correct? I have no confidence in my builder or the chain store right now.

What is the proper way and sequence to fix these problems?
I have a vinyl pool; watertemp 84.

Thanks so much.