Contract with Chinese manufacturer

We have been developing a household IoT device that can potentially be sold all over the globe. Initial prototypes have been creating strong demand and we'd like to launch a first round of large number manufacture with an improved design. We have contacted a firm based in China which we were referred to by personal contacts. Before we start working out the details though, I wanted to know what are typical pitfalls in your experience for a deal like that? Do we need to hire a Chinese attorney? Thanks for your advice