'Modern Family' Star Sarah Hyland -- I've Been BALLIN' Since I Was 5

"Modern Family" star Sarah Hyland has been makin' BANK since she was 5 years old ... but the actress tells TMZ she's not an IDIOT when it comes to saving her cash.

FYI -- Hyland's first acting gig was playing Howard Stern's daughter in "Private Parts" ... and the money train's been rolling strong ever since.

But Hyland says she's making damn sure she doesn't end up broke ass broke ... like Hammer or Lindsay Lohan.

We're thinkin' the chick who plays Lily on Sarah's show should take notes.