The verdict
For a small B2B or SaaS team, I'd pick Help Scout. You can set it up in a day, there is a free plan, and the bill is easier to predict. Pick Intercom if support volume is growing faster than headcount, your questions are mostly routine, and your help content is good. Fin could then pay for itself.
Intercom has two cost lines, seats and resolved outcomes, and the step up on higher tiers can be large. Help Scout bills its AI agent per resolution too, so work out expected volume in either. Whichever you choose, the AI is only as good as your help content.