GoPro Remo for $16.98 (Flash Sale for $15.99 until 10/10/19, 10PM PT). I got free shipping because I was buying other stuff too (I think always free for orders of $49+) but shipping is $5.99 for a la carte.
The remote is garbage but it's pretty cheap now (b/c discontinued).
The real kicker: If you're lucky, you'll get a DOA (like I did) and when I went through GoPro support (https://gopro.com/help/ContactUs
), they sent me a Smart Remote (https://gopro.com/en/us/shop/acce...E-002.html
) because the Remo is "Out of Stock" (but actually discontinued). But it seems like good part of the batch that Dick's Sporting Goods got is DOA, judging from the reviews and my own experience. So $16.98 + some inconvenience for a Smart Remote, sounded good to me.
On top of all that, GoPro support sent me a 15% discount code for a HERO7 Black for the inconvenience.
Smart Remote (https://gopro.com/en/us/shop/acce...E-002.html
) is compatible with HERO5/6/7/8 Black's, HERO5 Session, and Fusion. In addition, it supposedly works with all GoPro models with wireless capabilities, including the HERO3/3+, which is specified in a bullet on the website.