Business talks revolve around numbers. Chinese groups by 万 (wàn, 10k) and 亿 (yì, 100M), which differ from thousand/million/billion.
Big Numbers
一万 = 10,000; 十万 = 100,000; 一百万 = 1,000,000; 一亿 = 100,000,000. Quotes often sound like 这个项目大概三百万 (this project is around 3 million).
Percent & Multiples
百分之二十 = 20%; 增长了一倍 = +100%; 翻两番 = quadruple (4×).
Currency & Terms
RMB is 元/块 (spoken); USD 美元; HKD 港币; EUR 欧元. Frequent trade terms: 单价 (unit price), 总价 (total), 含税/不含税 (incl./excl. tax), FOB / CIF.
Tip
When hearing 个、十、百、千、万、十万、百万、千万、亿, mentally count the zeros to avoid order-of-magnitude mistakes.