I'm currently embarking on a new phase of research that requires some incredibly specific chemical compounds, and they aren't readily available off-the-shelf. I'm starting to explore custom synthesis services but haven't had much experience with them before. The thought of entrusting such crucial materials to an external party makes me a little nervous, especially regarding purity and delivery times. Has anyone here had good experiences with custom synthesis for their research chemicals? What should I look out for, or what questions should I be asking potential providers to ensure a successful outcome?