The soft constraints are the ones you can adjust without selling out your standards.

Lab choice. You might prefer a lab that's close to your warehouse, but if there's a better lab across the country, you can work with them. Shipping samples is easy.

Turnaround time. Sometimes you need results in a week. Sometimes you can wait three. Know your timeline and find a lab that matches it.

Report format. Some labs give you a one-page COA. Others give you a 20-page report. The longer one is better, but if the COA includes all the key data, you can work with it.

Testing frequency. You don't need to test every single batch if you're buying from a manufacturer you trust. But you should test random batches to confirm consistency.

The point is: you have room to negotiate. But you can't compromise on the core data.