II got caught in the east coast blackout (2003?) with less than $20 cash. With ATMs down, I had to make due with that. Since then, I have carried $100. Been pretty good about not touching it unless it is a true emergency. I keep it separate from the wallet, in case some thug with a weapon demands "street tax".

I don't drive. All mass transit. In your case, $200 sounds prudent.

Good thing you were ETS