What if I don't like the deal offered to me? Can I decline? Will this put me out of favor for future deals?

Yep, you can decline! Every single sponsorship is opt-in; you're only ever obligated to produce content for a deal you agreed to. Even if your account is inactive for years or you decline most offers you get, it's all the same to us!

Being upfront is the best policy here - whenever possible, decline the deal or ask to cancel early on in the campaign chat if something comes up. This is much more preferable than failing to communicate later on ("ghosting").