You have 200 Instagram followers. You don't need a mailing list yet, right? Wrong. You need one now, while those 200 people actually care.
The math
Instagram shows your posts to ~10% of followers. Email reaches ~40%. A mailing list of 50 real fans is worth more than 500 Instagram followers who might see your post.
One month free. Then $30/mo.
Custom band website, designed in 48 hours.