The person handing you the deposit is thinking about one thing: what happens to his money if the site goes quiet. Your website answers before he asks, who pays what, when, and what he already holds in his hand. From €450.
Write out how you split a job, from foundation to handover, and which payment closes each piece. The page is built from that. Where a stage cannot carry a fixed figure, we write it as a range and say what it depends on, instead of hiding it.