For most professional content, numerals (8%) are clearer and faster to read than written-out percentages (eight per cent). Use words only at the very start of a sentence, where a numeral would look awkward.
Acknowledge the risk plainly, then immediately follow with context. Write about what reduces that risk, what questions to ask or what steps a reader can take. Honesty about risk builds trust.
Rounding is perfectly acceptable when doing so does not change the practical meaning. For example, “$4,800 per year” is more readable than “$4,817.43”. Be transparent when approximating and never round in a way that misleads.
Write about costs in the context of outcomes. Instead of listing a fee in isolation, frame it alongside the value delivered or the problem solved. “Our fee covers the full debt recovery process from the initial letter through to legal escalation if required” is far more persuasive than a bare figure.
Assume your reader is intelligent but not industry-trained. Explain terms the first time you use them, use real-world examples and avoid condescending words like “simply” or “obviously”, which imply the reader should already know. Respect their intelligence while meeting them where they are.