not really…
the bill of sale is just there to ensure that you are getting a clean title…or some what clean.
It’s just to confirm what the seller has said about the car and what’s officially on record. For example, any liens, outstanding fines etc… will show up on the bill of sale.
The 6 day stuff, can also be used in such a way that if you find items on the car that wasn’t specified in the sale, you can terminate the transaction and get your money back.
(correct me if I’m wrong here)
Essentially it’s just used as a buffer to prevent a sale/purchase from going horribly wrong.