A smart consultant will include milestones like this in the contract: not just milestones for what they are expected to deliver, but milestones for when the cli

A smart consultant will include milestones like this in the contract: not just milestones for what they are expected to deliver, but milestones for when the client is expected to pay them, as well as milestones for when third parties (and/or the client) are expected to provide additional input/data/opinions. The contract should also describe what happens when those milestones are not met, e.g. for every day that milestone X is not met, then milestone Y will be pushed back accordingly, or the cost for Z will go up by some amount. A well written contract should make it almost irrelevant whether you're getting paid hourly or for a fixed cost, because you (and the client) are covered either way.