@lookingaround Thank you for the comments.
My explanation for the law enforcement cost increase was that was the number the County Sheriff charges to Cupertino. I guess it's more costly to setup the in house police department at first, but the running cost should be lower than what the County Sheriff charges. But it's just a guess, I would love to see a research to compare the two options.
For sales tax, in a perfect world, each city should receive the sales tax from their residents. For each $100 on taxable spending, the city should receive $1 (the other $8 goes to the state, county, etc). Cupertino should receive only $60K per month or $720K per year if average resident spending is $100 per month. $9M sales tax is equivalent to $1250 non grocery spending per resident (not per household) per month. I don't know about other families, but my family should be much lower than this number. I think even $9M sales tax for Cupertino is still higher if we go to a fairer system.
My suggestions are not the most important things. Cupertino verified voters' voice is more important. I am glad my suggestion 1 and 2 made the top 2, which were also surpassed 55% of participated registered voters. I am quite glad with this results. The results were published here.