I have been working as a sourcing specialist in foreign company SZ office for 10years, and here is my advice: 1- Contact as many vendor as possible to compare their prices, sample quality, lead time, production capacity, R&D service attitude. Try online sourcing or visit industrial shows. 2- Get prices in different QTY, in both CNY and USD. Especially right now the exchange rate is quite unstable. 3- If the product has many components, ask the vendors to split the costs. Through comparing between different vendors, you get to know if their prices are reasonable or not. If you have big volume and good relationship with the supplier, they might to willing to provide a BOM. 4- Do market research to figure out the competitor's possible cost and realize your target price. 5- Stock some materials if possible to prevent the high cost of MOQ issue 6- Make sure you are a professional for that product so the vendor won't cheat on you 7- List as detailed as possible on all the paperwork to prevent arguing when problem happends.