Instead of paying $3 for subscriber, you can youtube ads for your channel, or you can hire freelancer for youtube seo.
Search on upwork or Google for top youtube seo company.
This will bring you genuine subscriber and viewer to your channel according to your niche.
OP hs not sent single cent and will not send a single cent so OP has no loss and do not need to make youtube marketing by ads service or do not need to search any worker from upwork, freelancer etc.