I think it'd be a dumb idea all around. It is never a good thing, IMHO, to mix money relationships with familial relationships.
If anything goes wrong with the "loan", you risk souring the relationship with your parents. It's one thing if they're willing to give you the money as an early inheritance, but it's quite another if it's structured as a loan with an expectation of payback.
If anything goes wrong with the "loan", you risk souring the relationship with your parents. It's one thing if they're willing to give you the money as an early inheritance, but it's quite another if it's structured as a loan with an expectation of payback.