I know Guinness had gone away from certifying longest locs/braids record because they really can't determine if it's 100% real hair.

I remember seeing a YT vid of a girl who had roughly bra strap length hair and they put in extension braids that were floor length. Those products are definitely available to purchase. It took 12 hours with two girls working.

It looked beautiful but of course it was not all her real hair.