If you're only sending a small amount of desirable transactional email, you're the perfect model of a good sender and your blacklist risk will be vanishingly low. Sending from a shared IP will still expose you to the behavior of the other customers using it (like a VPS, you'll have neighbors). We actively police our shared IPs for bad sender behavior.
Dedicated IP packages won't be affected by the sending habits of other users. They are more cost-efficient for high-volume senders, but we do have dedicated IP tiers starting at the $80/mo. mark, which allows up to 100k mails a month.
With either option, we're always happy to work with you if you're having deliverability issues - and that includes checking IPs for blacklist status.