If I paid $15,000 cash for a car after saving for 15 years from gifts I was going to use for a big trip, the dealer sent form 8300 to gov'e, will this trigger an audit?

No, the IRS does not penalize you for saving money. They only care that you report income. Gifts received are not taxable income. If applicable, the gift tax is on the giver, not the recipient.

I wondered though would this trigger an audit.  I heard that it can since they put this form in some database to track cash amounts over 10,000.

It should not trigger an audit. If anyone would be audited it would be the business.. Realistically, the IRS does not know how you got the cash, it could be someone else lending you the money.

Hi, I’m a first year international student with no prior history of having a job. Will I get in trouble with the IRS if I bought a car with the $14,000 sent by my mother through my account?