2) Do seek advice from experts, such as the ACLU: https://www.aclu.org/drug-law-reform-immigrants-rights-racia...
3) Do not lie to police officers; it's a crime. A defense lawyer in this video advised not to talk to police at all if you are being investigated; you could misspeak (esp. under stress), be misunderstood, be taken out of context, the officer could misremember, etc. I have no idea if he's a crank or if it's good advice: https://www.youtube.com/watch?v=6wXkI4t7nuc
If he's going to arrest you it's probably best not to lie though. You can always say I'm not sure.
If you do have more than $1,000 in cash don't allow him to search your car.
Do not talk to the police, ever! If they arrest you, you only ask for the reason of the arrest and for legal counsil (a lawyer) and nothing more!
If they give you a ticket, keep your mouth shut, receive it and present it to a lawyer.
Do not consent to a search, ever! Even if you think you have nothing on you!
The police is not your friend!
Of course, as others have said, it's probably best to seek advice from a group that focuses on this topic - perhaps Flex Your Rights.
But when in doubt, definitely don't answer. "Officer, I prefer not to discuss money right now" is a completely reasonable answer that most cops will respond to with an understanding nod. If they don't, just calmly tell them you aren't sure what questions to answer until you have a lawyer present. Again, totally reasonable answer.
You should also not listen to me, though I think you'll find the ACLU provides the same advice.