Bring a list. Embarrassment makes everyone forget things, including you.

Test one thing at a time. It feels slower and it is the only way to learn anything. Not on methenolone enanthate but the pattern is familiar.

Written confirmation email after every phone call. Cheapest insurance there is. Not on distance sale in the EU but the pattern is familiar.

Stupid question: how do you know whether what is in the vial matches the label at all?

Photograph everything before you open it. Ten seconds, settles most disputes.

This is the correct amount of effort for a thread like this.

Daylight, no flash.

An inconclusive account is useful if it stops the next person mistaking a story for a controlled comparison.