The Model 3 SR in China is ~$33000USD and in the US (after tax credit), about $34000. Tesla is aiming for a much lower cost to produce... they've stated 50% COGS of the Model 3, which would put its cost at about $18000 USD. Their goal is to achieve > 20% gross margin, which would still be achievable at a selling price of $25K USD.
1. Less than a handful. $25k brings several options.
2. To effectively be a $20k car EVs have an advantage because of their tax subsidies. {Base Price} - {Tax Credit} < $20,000 is plausible. It's impossible to say who will qualify or how big of a tax credit US customers will have by the time this would launch.
Now do the math for now expensive the gas is for that in LA going out to the next ten years assuming ten miles a day commute during the week and 30 miles on weekends.
With how the Hoover dam and others are looking as well as taking into account a rising number of people that will want to charge EVs, maybe you want to do some scenarios around electricity pricing as well.