Good morning friends! This sweet little annual originated with my parents, many years ago. It is a self seeding annual. We always called it a black Eyed susan, but it's not a Rudbeckia. It grows 3 to 5 feet and blooms all summer. One year, we had a couple of them reach 7 feet! Thank you for looking!!
The flower


Stems




Leaves

It reminds me of Helianthus of some sort.

* Editing my post to add a couple of links for Helianthus that are found in S.C.

Purple-disk Sunflower (Helianthus atrorubens)
https://uswildflowers.com/deta...

Sunroots (Helianthus tuberosus)
https://uswildflowers.com/imag...

https://uswildflowers.com/deta...

Compare with dune sunflower.
(Helianthus debilis)

Don't know why I didn't think of Dune Sunflower (Helianthus debilis) which is also found in S.C.

https://uswildflowers.com/deta...

Stone and Lin, the data base lists Dune Sunflower as a vine. This is not a vine.

I grow Dune Sunflower and it is not a vine; info in the database is in error.

I'm only slightly familiar with Helianthus debilis but there are five subspecies which vary widely in habit from sprawling groundcover types to tall erect plants to over 6 feet.