3-5 bonuses is the sweet spot. Too few feels underwhelming. Too many feels overwhelming and devalues your main offer. Quality over quantity.
Use existing content first — repurpose your best blog posts, videos, or templates as bonuses. Creating bonuses from scratch should be a last resort.
Bonuses work because of perceived value and the fear of missing out. When the total bonus value significantly exceeds the product price, buying feels like a no-brainer.