I have a great idea for a phone accessory that has never been done before. I don't have thousands of dollars to patent the idea, so my idea was to try and find a Chinese manufacturer to produce my accessory. Would I need a prototype first? Would a NDA help in protecting my idea until I can afford a patent?
A prototype is a good start, plus it will allow you to get feedback from consumers before spending money to produce a larger batch. You can use services like Maker's Rowe to find domestic producers or even try to 3d print your initial prototype. If your idea is great you might consider gaining resources through kickstarter or quirky.